Patent Publication Number: US-2016229724-A1

Title: Filter system for a fluid

Description:
FIELD OF THE INVENTION 
     This invention relates to a filter system for a fluid, such as a filter system for the water in a fish aquarium. 
     BACKGROUND OF THE INVENTION 
     Today, there are many different applications where a fluid needs to be filtered. In many commercial, industrial, municipal and residential applications and processes, a fluid, either a liquid or a gas, needs to be filtered. The kind of fluid can vary. The fluid can be but is not limited to: fresh water, salt water, brine, an aqueous mixture, a chemical, a food mixture, a liquid mixture, milk, a juice, a soft drink, an alcohol, etc. Many municipalities have water treatment plants that filter and treat drinking water, storm water, waste streams, etc. Many homes and some small businesses have a fresh water and/or a salt water aquarium. Aquariums are manufactured in various sizes from 10 gallons to 1,500 gallons or more. Regardless of the size of the aquarium, all aquariums need the water filtered on a continuous basis. 
     In some of the above mentioned applications and processes, a portion of the fluid is removed from a container or tank and is routed to a filtering system where foreign particles, debris and/or waste is filtered out of the fluid. In addition, the fluid interacts with biological media to neutralize the harmful chemicals created by organisms in the aquarium. The clean fluid is then reintroduced back into the container or tank or into some part of the application or process. A home aquarium is a good example of one such application where water may be continuously filtered using a filtering system. The filtering system can be hidden from view. Water in the fish aquarium becomes tainted with food particles, algae growth, fish waste, etc. over time. A portion of this water is skimmed off from the upper surface of the water in the aquarium and is routed to a filtering system which is usually situated in a cabinet located below the aquarium or on lower level, such as in the basement. The filtering system can vary in design and construction. Usually, the filtering system has two or more compartments in which a particular filtration task is performed. The filter system can be set up to provide micro particle filtration, biological filtration and aeration. 
     Now, a filter system for a fluid has been invented. This filter system is especially useful for a fish aquarium. The filter system is sized to fit into a cabinet which supports the aquarium so that it is out of sight yet still provides easy access when one needs to check on the filter sock and/or the biological filer components. 
     SUMMARY OF THE INVENTION 
     Briefly, this invention relates to filter system for a fluid and is especially useful as a filter system for a fish aquarium. The filter system includes a sock tank having a top wall, a bottom wall and at least one sidewall connecting the top wall to the bottom wall to form an enclosure. The top wall has an inlet formed therethrough which is fluidly connected to a container holding a large quantity of fluid, such as a fish aquarium. An outlet is spaced apart from the inlet. A bracket is secured to an interior surface of the sock tank and a filter sock is removable attached to the bracket. The bracket positions the filter sock adjacent to the inlet to provide particle filtration of incoming fluid. The filter system also includes a first fluid connector which has a first end attached to the outlet of the sock tank and a second end. The filter system further includes a baffle tank having a bottom wall connected to at least one sidewall to form an enclosure. The baffle tank has a first chamber in fluid communication with a second chamber. The first chamber has a top wall connected to the at least one sidewall. An inlet is aligned with the second end of the first fluid connector for receiving incoming fluid in a non-sealing relationship. The first chamber contains a bacteria culture for biological filtration of the incoming fluid. The second chamber has a top wall connected to the at least one sidewall and has an outlet through which fluid can be routed back to the container holding a large quantity of fluid the aquarium). The second chamber contains a quantity of filtered fluid. A first baffle is formed by at least a portion of the sidewall of the first chamber. The first baffle is joined to at least a portion of the sidewall of the second chamber. The first baffle extends downward from the top wall of the first chamber and has a lower end positioned above the bottom wall. A second baffle is formed in the second chamber and extends upward from the bottom wall and has an upper end positioned below the top wall of the second chamber. The lower end of the first baffle is located closer to the bottom wall than is the upper end of the second baffle. The first and second baffles allow filtered fluid from the first chamber to flow into the second chamber while controlling the fluid level in the first chamber. Lastly, the filter system includes a return conduit having a first end attached to the outlet of the baffle tank and a second end connected to the container holding a large quantity of fluid (the aquarium) whereby filtered fluid can be routed back into the container holding a large quantity of fluid (the aquarium). 
     A second embodiment of the filter system includes the addition of a reservoir tank having a top wall, a bottom wall and at least one sidewall connecting the top wall to the bottom wall to form an enclosure. The reservoir tank is capable of holding a larger volume of fluid that the second chamber of the baffle tank. The reservoir tank can also serve as a refugium, as a feeder fish compartment, as an evaporation tank, etc. This second embodiment also includes appropriate fluid connectors for connecting the baffle tank to the reservoir tank and for transferring the filtered fluid from the baffle tank back to the container holding a large quantity of fluid (the aquarium). 
     Other embodiments where a combination of two reservoir tanks are connected to the baffle tank, or a combination where a pair of sock tanks and a pair of baffle tanks are connected together, with or without a reservoir tank, can also be utilized. 
     The general object of this invention is to provide a filter system for a fluid. A more specific object of this invention is to provide a filter system which can be used with a fish aquarium to provide both particle filtration and biological filtration. 
     Another object of this invention is to provide a filter system utilizing a sock tank for particle filtration and a baffle tank, having first and second chambers, wherein the first chamber houses a bacteria culture for biological filtration and the second chamber provides a holding area for the filtered fluid. 
     A further object of this invention is to provide a filter system that is not sealed to outside air and which uses molded tank construction which is less susceptible to fluid leakage. 
     Still another object of this invention is to provide a filter system for an aquarium which is easy to assemble, which can fit into a cabinet below the aquarium so that it is out of sight, and still allow easy access when one needs to check on the filter sock and/or the biological filer components. 
     Still further, an object of this invention is to provide a filter system which is relatively inexpensive. 
     Other objects and advantages of the present invention will become more apparent to those skilled in the art in view of the following description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a fish aquarium. 
         FIG. 2  is a cross-section al view of a filter system including a sock tank connected to a baffle tank which in turn is connected to a reservoir tank. 
         FIG. 3  is a perspective view of a sock tank. 
         FIG. 4  is a cross-sectional view of the sock tank shown in  FIG. 3  taken along line  4 - 4 . 
         FIG. 5  is a top view of the sock tank. 
         FIG. 6  is a perspective view of a bracket which is secured to an interior surface of the sock tank for holding the filter sock in alignment with the inlet. 
         FIG. 7  is a top view of a piece of glass. 
         FIG. 8  is a vertical cross-section view of the filter sock shown in  FIG. 4 . 
         FIG. 9  is a top view of the collar to which the filter sock is secured and the collar has a grasping member. 
         FIG. 10  is a perspective view of a baffle tank. 
         FIG. 11  is a bottom view of the baffle tank shown in  FIG. 10 . 
         FIG. 12  is a cross-sectional view of the baffle tank shown in  FIG. 10  taken along line  12 - 12 . 
         FIG. 13  is a cross-sectional view of the baffle tank shown in  FIG. 10  taken along line  13 - 13 . 
         FIG. 14  is a top view of a grommet. 
         FIG. 15  is a top view of a piece of glass which can cover the enlarged opening formed in the first chamber of the baffle tank. 
         FIG. 16  is a top view of a piece of glass which can cover the enlarged opening formed in the second chamber of the baffle tank. 
         FIG. 17  is a top view of a basket which can rest on the abutments formed in the first chamber of the baffle tank. 
         FIG. 18  is a side view of the basket shown in  FIG. 17 . 
         FIG. 19  is a perspective view of a reservoir tank. 
         FIG. 20  is a top view of the reservoir tank shown in  FIG. 19 . 
         FIG. 21  is a top view of a piece of glass. 
         FIG. 22  is a side view of a baffle tank and a reservoir tank fluidly connected together by a second fluid connector. 
         FIG. 23  is a side view of a sock tank, a baffle tank and a reservoir tank wherein the baffle tank and the reservoir tank are fluidly connected together by a second fluid connector positioned at an elevated height compared to its location in  FIG. 22 . 
         FIG. 24  is a side view of a filter system which includes a sock tank, a baffle tank and first and second reservoir tanks. 
         FIG. 25  is a side view of a filter system which includes a sock tank, a baffle tank and first and second reservoir tanks wherein the baffle tank and the first and second reservoir tanks are fluidly connected together by second and third fluid connector positioned at an elevated height compared to their location in  FIG. 24 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , a container  10  capable of holding a large quantity of fluid, such as a fish aquarium, is depicted. The container  10  can be formed from any known material. When the container  10  is a fish aquarium, it is normally formed from glass or acrylic. By “aquarium” it is meant a water-filled enclosure in which living fish or other aquatic animals and plants are kept. The container (aquarium)  10  can be mounted on and/or be supported by a cabinet  12 . The cabinet  12  can be stained to match ones personal decor so that it appears as a piece of furniture. The cabinet  12  can have one or more movable doors  14 . The doors  14 ,  14  can open and close via hinges, not shown, or be arranged to slide back and forth between an open and a closed position. Other means of constructing a movable door  14  are well known to those skilled in the art. Two hinged doors  14 ,  14  are shown in  FIG. 1 . Positioned above the container (aquarium)  10  is a canopy  16 . The canopy  16  finishes off the cabinet  12  and provides the cabinet  12  with the appearance of a fine piece of furniture. The canopy  16  also functions to hide various devices positioned above the container (aquarium)  10 . Although such devices are not shown, they could include a light fixture, a water discharge tube, one of more water inlet tubes, etc. Alternatively, the container (aquarium)  10  could be mounted on a stand or be build into a wall. 
     Although the invention will be explained relative to a filter system  18  for a container  10  capable of holding a large quantity of fluid, such as a fish aquarium, it should be understood that the filter system  18  can be used in various commercial, industrial, municipal and/or residential applications and processes. The fluid can vary and can be almost any liquid or gas. By “fluid” it is meant a continuous amorphous substance whose molecules move freely past one another and that assumes the shape of its container; a liquid or a gas. The fluid can be but is not limited to: fresh water, salt water, brine, an aqueous mixture, a chemical, a food mixture, a liquid mixture, a gas, milk, a juice, a soft drink, an alcohol, etc. By “brine” it is meant water saturated with or containing large amounts of a salt, especially sodium chloride; the water of a sea or an ocean. For simplicity, the invention will be explained as filtering water that has become contaminate by food particles, algae, fish feces and/or other foreign objects in a fish aquarium  10 . By “algae” it is meant any of various chiefly aquatic, eukaryotic, photosynthetic organisms, ranging from single-celled forms to the giant kelp. 
     Referring now to  FIG. 2 , a filter system  18  is shown which includes a sock tank  20  and a baffle tank  22 . An optional reservoir tank  24  is also shown. The filter system  18  also includes various fluid connectors for routing fluid to and from the filter system  18  and between the sock tank  20 , the baffle tank  22  and the reservoir tank  24 . All the necessary components will be explained below in detail. 
     Referring to  FIGS. 3-5 , dirty or contaminated water from the container (aquarium)  10  is routed through a discharge tube  26  to the sock tank  20 . The size of the discharge tube  26  can vary. Usually, the discharge tube  26  has an internal diameter of about 4 inches or less. The discharge tube  26  can be a flexible member or a right member. Desirably, the discharge tube  26  is a flexible member such as a plastic tube. The discharge tube  26  can be constructed out of various materials well known to those skilled in the art. The unclean, dirty or contaminated water can flow downward through the flexible discharge tube  26  and into the sock tank  20  under the influence of gravity. 
     The sock tank  20  can vary in size, shape and configuration. The sock tank  20  should be capable of holding a predetermined volume of fluid. The sock tank  20  is an integral member. By “integral” it is meant a complete unit, a whole. The sock tank  20  can be constructed in any manner known to those skilled in the art. For example, the sock tank  20  can be molded as an integral member, can be assembled from individual parts, be cast, be carved from a single member, etc. Desirably, the sock tank  20  is molded using various molding techniques well known to those skilled in the molding arts. When molded, the sock tank  20  will exhibit a one piece design with no seams, joins or welds. This is advantageous for it eliminates the possibility of having fluid leak out of the sock tank  20 . A molding apparatus that works well in molding the sock tank  20  is a rotational mold. 
     The sock tank  20  can be formed from various materials. Such materials can include but are not limited to: a plastic, a thermoplastic, a composite, an acrylic, glass, metal, a metal alloy, aluminum, tin, galvanized steel, copper, marine plywood, etc. The sock tank  20  can be constructed from a single material or from a combination of two or more materials. Desirably, the sock tank  20  is molded from High Density Polyethylene (HDPE). Other high density thermoplastics could also be used, such as High Density Polypropylene (HDPP). Alternatively, the baffle tank  10  can be molded from Low Density Polyethylene (LDPE), Low Density Polypropylene (LDPP). Another option is to mold the baffle tank  10  from other low or high density thermoplastics known to those skilled in the art. 
     Still referring to  FIGS. 3-3 , the sock tank  20  has a longitudinal central axis X-X, a vertical central axis Y-Y, and a transverse central axis Z-Z. The sock tank  20  also has a length l, a width w and a height h. The length l is measured along the longitudinal central axis X-X, the width w is measured along the vertical central axis Y-Y, and the height h is measured along the transverse central axis Z-Z. The length l, the width w and the height h of the sock tank  20  can vary in dimension depending upon the size of the container (aquarium)  10 . Nowadays, aquariums can range from 10 gallons to 5,000 gallons or more. Many aquariums mounted on a cabinet  12  can range from 50 gallons to about 5,000 gallons. When the sock tank  20  is used as part of the filter system  18  for a container (aquarium)  10 , it can have a length l of from between about 10 inches to about 50 inches, a width w of from between about 4 inches to about 25 inches, and a height h of from between about 16 inches to about 40 inches. Desirably, the sock tank  20 , when used to filter water from a fish aquarium  10 , has a length l of from between about 11 inches to about 30 inches, a width w of from between about 6 inches to about inches, and a height h of from between about 18 inches to about 30 inches. More desirably, the sock tank  20 , when used to filter water from the fish aquarium  10 , has a length l of about 20 inches, a width w of about 10 inches, and a height h of about 25 inches. The sock tank  20  should be sized, shaped and configured so that it can easily fit through one of the doors  14  formed in the cabinet  12 , when the container (aquarium)  10  is mounted on such a cabinet  12 . 
     The sock tank  20  has a top wall  28 , a bottom wall  30  and at least one sidewall  32  which connects the top wall  28  to the bottom wall  30  to form an enclosure  34 . Since the sock tank  20  is depicted as a rectangular member, it has four sidewalls  32 ,  32 ,  32  and  32 . One of the sidewalls  32  can be the front wall, another sidewall  32  can be the back wall, etc. The four sidewalls  32 ,  32 ,  32  and  32  can vary in size, shape and configuration. All of the four sidewalls  32 ,  32 ,  32  and  32  can be identical in size, shape and configuration or one or more of the sidewalls  32  can be different in size, shape and configuration. As shown, two of the sidewalls  32 ,  32  (the front and back walls) are of the same size and shape while the remaining two sidewalls  32 ,  32  are identical to one another but are smaller in size when compared to the first two sidewalls  32 ,  32 . 
     It should be understood that the sock tank  20  can have one or more sidewalls  32 . If the sock tank  20  had a cylindrical shape, with a circular cross-sectional diameter, then it would have a single sidewall  32 . The sock tank  20  could have two sidewalls  32 ,  32 , with each sidewall  32  being bowed outward, so that the sock tank  20  has a cross-sectional shape resembling an oval or a football. The sock tank  20  could also have three sidewalls  32 ,  32  and  32 , with the three sidewalls arranged to give the sock tank  20  a triangular cross-sectional shape. With four sidewalls  32 ,  32 ,  32  and  32 , the sock tank  20  could have a square or rectangular cross-sectional shape. With five sidewalls  32 ,  32 ,  32 ,  32  and  32 , the sock tank  20  could have a pentagon cross-sectional shape, etc. 
     The bottom wall  30  can be secured to the at least one sidewall  32  in any manner known to those skilled in the art so that a water proof seal is formed. By “waterproof seal” it is meant impervious to or unaffected by water. Molding the sock tank  20  is most desirable. However, the bottom wall  30  could be secured to the at least one sidewall  32  using glue, an adhesive, a co-adhesive, a heat bond, a pressure bond, a heat and pressure bond, a weld, etc., or a combination of two or more of the aforementioned bonding techniques. 
     Still referring to  FIGS. 2-5 , the sock tank  20  has an inlet  36 . The inlet  36  is shown as being formed in the top wall  28 . Alternatively, the inlet  36  could also be formed in an upper portion of the sock tank  20 , if desired. Desirably, the inlet  36  is formed in the top wall  28  so that if any water does leak out from this connection, it will simply pool on the top wall  28  of the sock tank  20  and then flow, via gravity, down into the sock tank  20 . The size, shape and configuration of the inlet  36  can vary. Desirably, the inlet  36  is a circular opening having an internal diameter d of about 4 inches or less, see  FIG. 5 . An adapter  38  can be fitted to the inlet  36  and project outward therefrom. The adapter  38  is designed to be connected to the discharge tube  26  from the container (aquarium)  10 . Various kinds and types of adapters  38  can be utilized, as is well known to those skilled in the art. The adapter  38  can be a slip fitting having a barbed exterior with is connected to the interior of the flexible discharge tube  26 . Alternatively, the adapter  38  can be tightly or snugly fitted to the inlet  36 . Other ways of attaching the adapter  38  can also be used including but not limited to a press fit, a threaded connection, a bayonet fit, etc. It should be understood that the filter system  18  does not utilize any high pressure seals that could leak over time. 
     The sock tank  20  also has an outlet  40  spaced apart from the inlet  36 . The outlet  40  can be formed through one of the sidewalls  32 . The outlet  40  should be located at a lower vertical location relative to the inlet  36 . The outlet  40  can be aligned at an angle to the inlet  36 . In  FIG. 3 , the outlet is aligned at about 90° to the inlet  36 . The size of the outlet  40  can vary but generally it is about the same size as the inlet  36 . As shown the outlet  40  is a circular opening having a diameter of about 4 inches or less. 
     Referring now to  FIGS. 4 and 6 , the sock tank  20  further includes a bracket  42  secured to an interior surface  44  of the sock tank  20 . The bracket  42  can be constructed from various materials. Such materials include but are not limited to: almost any kind of plastic or thermoplastic, including high density polyethylene (HOPE), high density polypropylene (HDPP), low density polyethylene (LOPE), low density polypropylene (LDPP), polyvinyl chloride (PVC), ABS, etc. The bracket  42  can also be formed from metal, a metal alloy, aluminum, an aluminum alloy, or from some other material. A thin metal sheet that can be easily machined, punched, drilled, bent, etc. is desirable for forming the bracket  42 . The bracket  42  can be formed, molded, welded, be machined or be formed some other way known to those skilled in the art. 
     The interior surface  44  of the sock tank  20  can be the bottom of the top wall  28 . The bracket  42  is designed to be positioned adjacent to the inlet  36 . The bracket  42  can vary in size, shape and configuration. The bracket  42  can be secured to the sock tank  20  by various means known to those skilled in the art. One easy way to attach the bracket  42  is to use one or more screws (not shown) that pass through one or more holes  46  formed in the bracket  42 . Four small holes  46  are depicted in  FIG. 6 . The four small holes  46  align with four small holes  47 , see  FIG. 5 , formed in the top wall  28  of the sock tank  20 . The bracket  42  can be secured to the sock tank  20  with four screws passing through these holes  46  and  47 . Alternatively, plastic rivets (not shown) can be used in place of the screws. The plastic rivets will not degrade due to the presence of water and they do not chemically affect the water. 
     The bracket  42  is depicted as being U-shaped with first and second, spaced apart legs,  48  and  49  respectively. A large aperture  50  is formed through the first leg  48  and a C-shaped member  51  is formed in the other leg  49 . The large aperture  50  is aligned with the inlet  36  when the bracket  42  is secured to the interior surface  44  of the sock tank  20 . The large aperture  50  should be larger than the internal diameter d of the inlet  36  so as not to obstruct fluid flow therethrough. The C-shaped member  51  is sized to support a sock filter  52  in a vertical orientation, parallel to the vertical central axis Y-Y. The first and second legs  48  and  49  respectively, of the U-shaped bracket  42  can be spaced apart by any desired distance. Desirably, the first and second legs  48  and  49  respectively, are spaced about 1 inch apart. This spacing is a desirable feature of the filter system  18  for it enables incoming water to bypass the sock filter  52  in the event the sock filter  52  becomes clogged. 
     Referring again to  FIGS. 3 and 5 , the top wall  28  of the sock tank  20  has an enlarged opening  54  formed therethrough. The enlarged opening  54  provides easy access to the sock tank  20  such that a person can easily pass his or her hand and/or a portion of his or her forearm into the sock tank  20 . The enlarged opening  54  can vary in size, shape and configuration. The enlarged opening  54  is depicted as a square in  FIGS. 3 and 5  but could be a circle or some other shape, if desired. In  FIGS. 3 and 5 , the sides of the enlarged opening  54  can range from between about 3 inches to about 12 inches or more when the sock tank  20  is used as part of the filter system for an aquarium  10 . More desirably, each of the sides of the enlarged opening  54  is at least about 5 inches or more in dimension. 
     Referring now to  FIG. 7 , a piece of glass  56  is shown which is sized and shaped to cover the enlarged opening  54  formed in the top wall  28  of the sock tank  20 . The piece of glass  56  is depicted as being square sine the enlarged opening  54  is a square shaped opening. The piece of glass  56  is removable by lifting it upward and away from the enlarged opening  54 . One could use a different material other than glass, if one so desired. However, glass is a very common material that is relatively inexpensive, is resilient to water, comes in different thicknesses, can be cut into various shapes, has a certain weight to it so that it will remain in place on the top wall  28 , and is washable should it get dirty. 
     The primary function of the piece of glass  56  is to slow down, limit or prevent evaporation of water from the sock tank  20 . The filter system  18  is not a closed, sealed unit and therefore the water is exposed to the atmosphere. This means that water, in the form of a vapor, can escape from the sock tank  20 . By “vapor” it is meant the gaseous state of a substance that is liquid or solid under ordinary conditions. For many filtration systems, it is advantageous to limit evaporation so that the quantity of water in the entire system does not need to be replenished on a regular basis. 
     The thickness of piece of glass  56  can vary. When the sock tank  20  is used as part of the filter system  18  for a fish aquarium  10 , the thickness of the piece of glass  56  can range from between about 0.125 inches to about 0.5 inches. Desirably, the thickness of the piece of glass  56  can range from between about 0.2 inches to about 0.4 inches. More desirably, the thickness of the piece of glass  56  can be about 0.375 inches. 
     Referring again to  FIGS. 3 and 5 , one can see that a finger depression  58  is formed in the top wall  28 , adjacent to the enlarged opening  54 . The finger depression  58  is optional but serves a very useful purpose. The finger depression  58  facilitates removal of the piece of glass  56  from the enlarged opening  54 . The finger depression  58  can vary in size, shape and configuration but should be large enough to accommodate a person&#39;s index finger up to the first knuckle. 
     Still referring to  FIGS. 3-5 , one will notice that the sock tank  20  also has a rim  60  which surrounds the top wall  28 . By “rim” it is meant a border, edge or margin of an object. The rim  60  functions to create a well  62  in the top wall  28 . By “well” it is meant an enclosed space for receiving and holding something, such as water. The depth of the well  62  can vary. Any incoming water that does not pass through the inlet  36  but instead splashes onto the top wall  28  of the sock tank  20  can pool in the well  62 . This water would then be able to flow downward into the sock tank  20  via the first finger depression  58 . The piece of glass  56  can fit into the well  62 . 
     Referring now to  FIG. 4 , the sock tank  20  depicts the sock filter  52  attached to the bracket  42 . The sock filter  52  is designed to be easily and quickly attached and also be removed from the bracket  42 . The sock filter  52  is aligned with the inlet  36  and is held stationary, in a vertical orientation, parallel to the vertical central axis Y-Y. The sock filter  52  can be inserted into and be removed from the sock tank  20  via the enlarged opening  54 . The sock filter  52  is easily slid onto the C-shaped member  51  of the bracket  42 . 
     Referring now to  FIGS. 8 and 9 , the sock filter  52  is formed from a porous filter material that can filter particles of a predetermined size or larger. The openings in the porous filter material can vary. Sock filters are commercially available today with a wide range of filtering capabilities. For the filter system  18  used in a fish aquarium  10 , the sock filter  52  should be formed from a porous filter material that can filter particles having a size of from between about 1 to about 500 microns or more. Desirably, the sock filter  52  can filter out particles up to about 50 microns or larger in size. More desirably, the sock filter  52  can filter out particles up to about 100 microns or larger in size. Even more desirably, the sock filter  52  can filter out particles up to about 150 microns or larger in size. Other size sock filters  52  can also be utilized, if desired. The finer the filter material, the more particles it is able to filter out of the water. A 100 micron filter can filter particles as small as 100 microns in size from the incoming water and is suitable for most fish aquariums  10 . 
     The sock filter  52  should be constructed of a porous material known to those skilled in the art. The sock filter  52  is manufactured in the shape of a hollow, elongated tube  64  that has a first end  66  and an oppositely aligned second end  68 . The first end  66  is open while the second end  68  is closed. The hollow, cylindrical tube  64 , with its closed second end  68 , resembles a sock, hence the name “sock filter”. The porous filter material forming the hollow, elongated tube  64  can be sewn, stitched or be secured using some other known means to acquire its shape and create the closed end  68 . 
     Referring to  FIG. 8 , the first end  66  of the hollow, elongated tube  64  can be secured to a collar  70 . By “collar” it is meant any of various ring-like devices used to limit, guide or secure another part. The inner circumference of the open, first end  66  can be attached to the periphery of the collar  70  by an attachment  72 . Various attachment  72  methods can be used. The attachment  72  can be but is not limited to: a pressure seal, a heat seal, a heat and pressure seal, a mechanical device, a chemical bond, an adhesive, glue, a cohesive, a combination of two different attachment elements, etc. 
     Referring to  FIG. 9 , the collar  70  is shown having an internal diameter d; that can vary. The internal diameter d 1  can range from between about 2 inches to about 12 inches. Desirably, the internal diameter d 1  of the collar  70  ranges from between about 4 inches to about 7 inches. The collar  70  can be constructed from various materials. Desirably, the collar  70  is formed from plastic since plastic is easy to mold and is relatively inexpensive. The collar  70  also contains a grasping member  74 . The grasping member  74  can vary in size, shape and configuration. The grasping member  74  can be integrally formed with or be molded into the collar  70 . Alternatively, the grasping member  74  can be a separate member that is joined to the collar  70 . In  FIG. 9 , the grasping member  74  is depicted as a narrow handle that extends across a portion of the inner periphery of the collar  70 . The grasping member  74  is shown having a curved shape although any desired shaped could be used. The grasping member  74  is about 3 inches long and about 0.375 inches wide. The grasping member  74  provides a prominent handle whereby a person can hold and/or carry the sock filter  52  in a vertical orientation without having to grasp the porous filter material from which the sock filter  52  is constructed. 
     The sock filter  52  allows water to easily pass through the porous material from which it is formed while stopping the passage of particles which are larger than the pore size of the sock filter  52 . The collar  70  is sized to easily slide into the C-shaped member  51  of the bracket  42 . This arrangement allows the sock filter  52  to be quickly and easily attached to or be removed from the sock tank  20 . The bracket  42  will hold and position the sock filter  52  below the inlet  36  of the sock tank  20 . The incoming water will be directed into the interior of the sock filter  52  and will pass outward through the entirety of the porous filter material forming the elongated tube  64 . However, the sock filter  52  is spaced about 1 inch below the inlet  36  due to the U-shaped configuration of the bracket  42 . This means that a space or gap is present between the first end  66  of the sock filter  52  and the inlet  36 . This is very important, for in the event that the pores of the porous filter material, from which the sock filter  52  is constructed, become clogged, the incoming water can bypass the sock filter  52  and flow or trickle over the top edge of the collar  70 . This bypassed water will then be able to continue through the remainder of the filter system  18 . This feature will prevent a flood from occurring or the immediate need to shut down the entire filter system  18 . Many commercially available filter systems sold today do not have this feature. Closed canister filter systems do not have this capability. 
     The sock tank  20  serves to remove particles from the incoming water. This is important for it will prevent such particles from potentially clogging any bacteria culture that is situated downstream of the sock tank  20 . A bacteria culture is used to provide biological filtration. 
     It should be understood that the sock tank  20  does not contain any high pressure seals that could possibly leak over time. The sock filter  52  is capable of removing micro particles from the water to improve water clarity. The sock filter  52  can be easily changed without having to turn off any water return pump. In addition, the incoming water can bypass the sock filter  52  in the event that it gets clogged without disrupting the remainder of the filter system  18 . 
     Referring again to  FIG. 2 , the filter system  18  also includes a first fluid connector  76 . The first fluid connector  76  has a first end  78  attached to the outlet  40  of the sock tank  20  and a second end  80 . The first fluid connector  76  is hollow and can vary in size, shape and configuration. The first fluid connector  76  is depicted as an elbow although it could have some other configuration, if desired. By “elbow” it is meant something having a bend or angle similar to a person&#39;s elbow. The first fluid connector  76  can control the direction of fluid (water) flow leaving the sock tank  20 . 
     Referring again to  FIGS. 2, and 10-13 , the filter system  18  also includes a baffle tank  22 . The baffle tank  22  is an integral member. By “integral” it is meant a complete unit, a whole. The baffle tank  22  can be constructed in any manner known to those skilled in the art. For example, the baffle tank  22  can be molded as an integral member, can be assembled from individual parts, be cast, be carved from a single member, etc. Desirably, the baffle tank  22  is molded using various molding techniques well known to those skilled in the molding arts. When molded, the baffle tank  22  will exhibit a one piece design with no seams, joins or welds. This is advantageous for it eliminates the possibility of having fluid leak out of the baffle tank  22 . A molding apparatus that works well in molding the baffle tank  22  is a rotational mold. 
     The baffle tank  22  can be formed from various materials as where explained above for the sock tank  20 . Generally, the baffle tank  22  will be molded from the same material used to mold the sock tank  20 . Desirably, the baffle tank  22  is molded from High Density Polyethylene (HDPE), High Density Polypropylene (HDPP), Low Density Polyethylene (LDPE) or Low Density Polypropylene (LDPP). Another option is to mold the baffle tank  10  from other low or high density thermoplastics known to those skilled in the art. 
     Other high density thermoplastics could also be used, such as High Density Polypropylene (HDPP). 
     Referring now to  FIGS. 10-13 , the baffle tank  22  has a longitudinal central axis X 1 -X 1 , a vertical central axis Y 1 -Y 1 , and a transverse central axis Z 1 -Z 1 . The baffle tank  22  also has a length l 1 , a width w 1  and a height h 1 . The baffle tank  22  has a bottom wall  82  secured to at least one sidewall  84  to form an enclosure  86 . Four sidewalls  84 ,  84 ,  84  and  84  are shown in  FIGS. 10-12  which create a rectangular shape. Any number of sidewalls  84  can be used. A single sidewall  84  would produce a circular enclosure  86  such as a cylinder. The bottom wall  82  can be secured to the at least one sidewall  84  in any manner known to those skilled in the art provided a water proof seal is formed. By “waterproof seal” it is meant impervious to or unaffected by water. Molding the baffle tank  22  is most desirable. However, the bottom wall  82  could be secured to the at least one sidewall  84  using glue, an adhesive, a co-adhesive, a heat bond, a pressure bond, a heat and pressure bond, a weld, etc., or a combination of two or more of the aforementioned bonding techniques. 
     The baffle tank  22  has a first chamber  88  in fluid communication with a second chamber  90 , see  FIGS. 10 and 12 . The first chamber  88  can vary in size, shape and configuration. The first chamber  88  can be smaller, equal to or be larger in volume than the second chamber  90 . Generally, the first chamber  88  is smaller in volume than the second chamber  90  when the baffle tank  22  is utilized as part of the filter system  18  for a fish aquarium  10 . One reason for this it that the first chamber  88  can function to hold a high surface area, bacteria culture which can provide biological filtration while the second chamber  90  can function as a reservoir where clean water is retained until it is pumped back into the aquarium  10 . A reservoir should be capable of holding a large volume of fluid, generally a greater amount, than is present in the biological filtration chamber. 
     The first chamber  88  has a top wall  92  with an enlarged opening  94  formed therein. The first chamber  88  also has an inlet  96  for receiving incoming fluid from the sock tank  20  in a non-sealing relationship. The size, shape and configuration of the inlet  96  can vary. Typically, the inlet  96  has a diameter of about 4 inches or less. The second end  80  of the first fluid connector  76  is connected to the inlet  96 . 
     Still referring to  FIGS. 10-13 , the inlet  96  is shown being formed in and extending through the top wall  92 . However, the inlet  96  could be formed in and extend through an upper portion of the sidewall  84 , if desired. One advantage of forming the inlet  96  in the top wall  92  is that the connection between the first fluid connector  76  and the inlet  96  does not have to be a water tight seal. The baffle tank  22  is not designed to be part of a pressurized, closed filtration system. This means that no water tight seals are required in the filter system  18 . This is another advantage the present filter system  18  because one does not have to rely on water tight seals that can fail over time. 
     Still referring to  FIGS. 10-12 , the second chamber  90  has a top wall  98  with an enlarged opening  100  formed therein. The second chamber  90  also has one or more outlets  102 . Desirably, the second chamber  90  has at least two outlets  102 ,  102 . More desirably, the second chamber  90  has three or more, spaced apart, outlets,  102 ,  102  and  102 . Three outlets  102 ,  102  and  102  are depicted in  FIG. 10 . Each of the three outlets  102 ,  102  and  102  extends through the thickness of the top wall  980 . When two or more outlets  102 ,  102  are present, one outlet  102  can function as a fluid outlet so that the clean filtered water in the second chamber  90  can be pumped out and be directed back into the container holding a larger quantity of fluid (the aquarium  10 ) or into the reservoir tank  24 . 
     Referring to  FIGS. 2 and 12 , a pair of electrical pumps  104 ,  104  is depicted positioned in the bottom of the second chamber  90 . Each of the pumps  104 , 104  functions to pump clean water, under pressure, out of the second chamber  90  of the baffle tank  22 . The pressurized, filtered fluid (water) can then be routed back the container holding a large quantity of fluid (the aquarium)  10 . The pressurized fluid can be directed through a return conduit  106  connected to the output side of each pump  104 ,  104 . Two return conduits  106 ,  106  are shown since two pumps  104 ,  104  are utilized. Some aquariums  10  use only a single pump  104 . Each return conduit  106  can be a flexible tube or hose, a rigid tube or hose or the return conduit can be hard plumbed using any material known to those skilled in the art. Each return conduit  106  can vary in diameter. Usually the diameter of each of the return conduits  106 ,  106  is about 0.25 inches. Each of the return conduits  106 ,  106  passes through one of the outlets  102 ,  102  and is fluidly connected at its opposite end to the aquarium  10  or to another tank. The outside diameter of each of the return conduits  106 ,  106  is approximately equal to the inner diameter of one of the outlets  102 ,  102  so as to limit or prevent evaporation of water from the second chamber  90 . By “evaporate” it is meant to convert or change into a vapor. 
     Referring to  FIGS. 10, 12  and - 14 , each of the pumps  104 ,  104  has an electrical cord  108  that supplies electricity to operate the respective pump  104 . Each of the electrical cords  108 ,  108  can pass through a third outlet  102 . The third outlet  102  can be covered with a grommet  110 . By “grommet” it is meant a reinforced member through which an electrical cord can pass. The grommet  110  can be formed from a pliable and flexible material, such as rubber. Desirably, the grommet  110  is formed as a thin rubber membrane which completely closes the outlet  102 . The grommet  110 , see  FIG. 14 , can contain one or more narrow slits  112 . The slits  112  can be radially aligned like the spokes on a wheel. The slits  112  can intersect one another. The slits  112  allow each of the electrical cords  108 ,  108  to pass through the grommet  110 . Alternatively, one or more small apertures could be formed through the grommet  110  which are sized to allow the electrical cords  108 ,  108  to easily pass therethrough. The grommet  110  functions to block off a substantial portion of the outlet  102 . Such a design limits the amount of clean water that can evaporate from the second chamber  90 . 
     Referring again to  FIGS. 10 and 13 , the baffle tank  22 , as noted above, has a length l 1 , a width w 1 , and a height h 1  and each of these can vary in dimension. The length l 1 , can range from between about 18 inches to about 30 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . A length l 1  of less than about 28 inches works well when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the length l 1  is about 20 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . The width w 1  can range from between about 10 inches to about 24 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . A width w 1  of less than about 20 inches works well when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the width w 1  is about 16 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . The height h 1  can range from between about 12 inches to about 30 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the height h 1  can range from between about 14 to about 24 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the height h can range from between about 15 to about 22 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the height h 1  can range from between about 16 to about 20 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     The reason for the above ranges is that many filter systems for aquariums  10  are situated within a wooden or metal cabinet  12  located below the aquarium. Sometimes, the aquarium  10  rest on a stand or on the cabinet  12  such that the stand or cabinet  12  provides support for the aquarium  10 . The cabinet  12  can be designed and constructed to appear similar to a fine piece of furniture having one or more hinged doors  14 ,  14 . The cabinet  12  may also be decorated or include fancy trim pieces. By placing the filter system  18  within the cabinet  12 , one can hide the filter system  18  yet have easy access to it through the hinged doors  14 ,  14 . 
     Referring now to  FIG. 13 , the baffle tank  22  further includes a first baffle  114 . The first baffle  114  is integrally formed by at least a portion of the sidewall  84  of the first chamber  88 . By “baffle” it is meant a static device that regulates the flow of a fluid. The first baffle  114  is secured to at least a portion of the sidewall  84  which also forms the second chamber  90 . Desirably, the first baffle  114  extends across the inner diameter or width w 1  of the baffle tank  22 . The first baffle  114  extends downward from the top wall  92  of the first chamber  88  and has a lower end  116  positioned above the bottom wall  82 . The first baffle  114  has a height h 2 . The height h 2  of the first baffle  114  can vary. The height h 2  of the first baffle  114  can range from between about 3 inches to about 25 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the height h 2  of the first baffle  114  can range from between about 5 to about 20 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the height h 2  of the first baffle  114  can range from between about 8 to about 18 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the height h 2  of the first baffle  114  can range from between about 9 to about 15 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     The first baffle  114  extends downward from the top wall  92  but stops short of the bottom wall  82 . This distance can vary. For a baffle tank  22  having a height h of about 18 inches, the first baffle  114  should extend downward from the top wall  92  of the first chamber  88  a distance equal to at least about 40% of the height h of the baffle tank  22 . Desirably, the first baffle  114  should extend downward from the top wall  92  of the first chamber  88  a distance equal to at least about 50% of the height h of the baffle tank  22 . More desirably, the first baffle  114  should extend downward from the top wall  92  of the first chamber  88  a distance equal to at least about 60% of the height h of the baffle tank  22 . Even more desirably, the first baffle  114  should extend downward from the top wall  92  of the first chamber  88  a distance equal to at least about 70% of the height h of the baffle tank  22 . 
     The lower end  116  of the first baffle  114  is positioned a distance d 2  above the bottom wall  82 . The distance d 2  can vary. The lower end  116  of the first baffle  114  should be spaced a distance d 2  of at least about 3 inches away from the bottom wall  82  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the lower end  116  of the first baffle  114  should be spaced a distance d 2  of at least about 4 inches away from the bottom wall  82  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the lower end  116  of the first baffle  114  should be spaced a distance d 2  of at least about 4 inches away from the bottom wall  82  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the lower end  116  of the first baffle  114  should be spaced a distance d 2  of at least about 5 inches away from the bottom wall  82  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     Still referring to  FIG. 13 , the baffle tank  22  further includes a second baffle  118 . The second baffle  118  is integrally formed with at least a portion of the sidewall  84  of the second chamber  90 . The second baffle  118  is completely formed within the second chamber  90 . The second baffle  118  extends across the inner diameter or width w 2  of the baffle tank  22 . The second baffle  118  extends upward from the bottom wall  82  and has an upper end  120  positioned below the top wall  98  of the second chamber  90 . The second baffle  118  is also aligned approximately parallel to the first baffle  114 . Desirably, the second baffle  118  is aligned parallel to the first baffle  114 . The second baffle  118  is spaced apart from the first baffle  114 . The distance the first and second baffles.  114  and  118  respectively, are spaced apart from one another can vary. Typically, the first and second baffles,  114  and  118  respectively, can be spaced at least about 0.5 inches apart when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the first and second baffles,  114  and  118  respectively, can be spaced at least about 1 inch apart when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the first and second baffles,  114  and  118  respectively, can be spaced at least about 1.5 inches apart when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the first and second baffles,  114  and  118  respectively, can be spaced more than about 2 inches apart when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     The second baffle  118  has a height h 3 . The height h 3  of the second baffle  118  can vary. The height h 3  of the second baffle  118  can be less than, equal to or be greater than the height h 2  of the first baffle  114 . Desirably, the height h 3  of the second baffle  118  is equal to or greater than the height h 2  of the first baffle  114 . More desirably, the height h 3  of the second baffle  118  is greater than the height h 2  of the first baffle  114 . 
     The height h 3  of the second baffle  118  can range from between about 3 inches to about 25 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the height h 3  of the second baffle  118  can range from between about 5 to about 20 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the height h 3  of the second baffle  118  can range from between about 8 to about 18 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the height h 3  of the second baffle  118  can range from between about 9 to about 15 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     The second baffle  118  extends upward from the bottom wall  82  but stops short of the top wall  98 . This distance can vary. For a baffle tank  22  having a height h of about 18 inches, the second baffle  118  should extend upward from the bottom wall  82  of the second chamber  90  a distance equal to at least about 40% of the height h of the baffle tank  22 . Desirably, the second baffle  118  should extend upward from the bottom wall  82  of the second chamber  90  a distance equal to at least about 50% of the height h of the baffle tank  22 . More desirably, the second baffle  118  should extend upward from the bottom wall  82  of the second chamber  90  a distance equal to at least about 60% of the height h of the baffle tank  22 . Even more desirably, the second baffle  118  should extend upward from the bottom wall  82  of the second chamber  90  a distance equal to at least about 70% of the height h of the baffle tank  22 . 
     The upper end  120  of the second baffle  118  is positioned a distance d 3  above the bottom wall  82 . The distance d 3  can vary. The upper end  120  of the second baffle  118  should be spaced at least about 3 inches away from the top wall  98  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the upper end  120  of the second baffle  118  should be spaced at least about 3.5 inches away from the top wall  98  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the upper end  120  of the second baffle  118  should be spaced at least about 4 inches away from the top wall  98  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Even more desirably, the upper end  120  of the second baffle  118  should be spaced at least about 5 inches away from the top wall  98  when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . 
     Referring again to  FIGS. 10 and 13 , when viewed from the front, the first baffle  114  forms a groove  122  in the exterior surface of the baffle tank  22 . The groove  122  can vary in shape. A V-shaped groove  122  is depicted. However, a groove  122  could be a U-shaped groove  122  or any other shape. The first baffle  114  extends downward from the top walls  92  and  98 . Therefore, the groove  122  extends down from both of the top walls,  92  and  98 . The first baffle  114  also forms a portion of a sidewall  84  to the first chamber  88  and a portion of a sidewall  84  to the second chamber  90 . The sides of the first baffle  114  can be slightly bowed outward so that they exhibit a convex configuration. By “bow” it is meant bent, curved or arched. This slight bow facilitates removing the baffle tank  22  from the mold. The second baffle  118  forms an inverted groove  124  in the baffle tank  22 . The inverted groove  124  can vary in shape. The inverted groove  124  can be a V-shaped groove, a U-shaped groove, etc. The second baffle  118  extends upward from the bottom wall  82 . Therefore, the inverted groove  124  extends up from the bottom wall  82 . The sides of the second baffle  118  can also be slightly bowed outward so that they exhibit a convex configuration. This slight bow facilitates removing the baffle tank  22  from the mold. 
     The pair of grooves  122  and  124  provides the baffle tank  22  with a unique visual exterior appearance. The pair of grooves  122  and  124  can be equal in size and appearance or can differ in size and appearance. Desirably, the pair of grooves  122  and  124  is identical in size and appearance. 
     Referring again to  FIG. 13 , one can clearly see that the grooves  122  and  124  extend completely across the width w 1  of the baffle tank  22 . 
     In order to function properly and maintain a predetermined water level in the first chamber  88 , the lower end  116  of the first baffle  114  is located closer to the bottom wall  82  than is the upper end  120  of the second baffle  118 . The water level in the first chamber  88  will be dictated by the height h 3  of the upper end  120  of the second baffle  118  assuming sufficient water has been introduced into the first chamber  88 . A basket or container, not shown, filled with a plurality of small, high surface area members, such as ceramic spherical balls, can be placed in the first chamber  88  to create a bacteria culture for biological filtration. By “ceramic” it is meant any of various hard, brittle, heat and corrosion resistant materials made by shaping and then firing a nonmetallic mineral, such as clay, at a high temperature. The incoming unclean, dirty or contaminated water from the aquarium  10  is directed downward so that it passes around and between these ceramic spherical balls. This action cleanses the contaminated fluid (water) of bacteria and other harmful chemicals, for example ammonia can be converted to less dangerous elements. The unique structure of the first and second baffles,  114  and  118  respectively, ensures that any basket or container, filled with such a bacteria culture, and present in the first chamber  88  will be completely submerged in water. This will be true even if the water level in the second chamber  90  goes down due to evaporation or some other reason. In essence, the first and second baffles,  114  and  118  respectively, control the fluid (water) level in the first chamber  88 . In order for the biological filtration to work properly, the bacteria culture should be at least partially submerged in a fluid (water). Desirably, the bacteria culture should be completely submerged in a fluid (water). 
     Still referring to  FIG. 13 , it should be understood that the first and second chambers.  88  and  90  respectively, are fluidly connected via the first and second baffles,  114  and  118  respectively. The first and second chambers,  88  and  90  respectively, have an opening  126  located therebetween. 
     Still referring to  FIG. 13 , the lower end  116  of the first baffle  114  is positioned above the bottom wall  82  by a first distance d 2  and the upper end  120  of the second baffle  118  is positioned below the top wall  98  of the second chamber  90  by a second distance d 3 . The first distance d 2  can be approximately equal to the second distance d 3 . Alternatively, the first distance d 2  can be greater than the second distance d 3 . Another alternative is to have the first distance d 2  be less than the second distance d 3 . 
     Referring now to  FIGS. 15 and 16 , first and second pieces of glass,  128  and  130  respectively, are shown. The first piece of glass  128  is sized and shaped to cover the enlarged opening  94  formed in the top wall  92  and cover the first chamber  88 . The first piece of glass  128  is removable by lifting it upward and away from the enlarged opening  94 . The second piece of glass  130  is sized and shaped to cover the enlarged opening  100  formed in the top wall  980  and cover the second chamber  90 . The second piece of glass  130  is removable by lifting it upward and away from the enlarged opening  100 . 
     One could use a different material other than glass, if one so desired. However, glass is a very common material that is relatively inexpensive, is resilient to water, comes in different thicknesses, can be cut into various shapes, has a certain weight to it so that it will remain in place on the top walls  92  and  98 , and is washable should it get dirty. 
     The primary function of the first and second pieces of glass,  128  and  130  respectively, is to slow down, limit or prevent evaporation of water from the first and second chambers,  88  and  90  respectively. 
     The thickness of each of the first and second pieces of glass,  128  and  130  respectively, can vary. When the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 , the thickness of each of the first and second pieces of glass,  128  and  130  respectively, can range from between about 0.1 inches to about 0.5 inches. Desirably, the thickness of each of the first and second pieces of glass,  128  and  130  respectively, can range from between about 0.3 inches to about 0.4 inches. More desirably, the thickness of each of the first and second pieces of glass,  128  and  130  respectively, can be about 0.375 inches. 
     Referring again to  FIG. 10 , a first finger depression  132  is shown formed in the top wall  92 , adjacent to the enlarged opening  94 . The first finger depression  132  is optional but serves a very useful purpose. The first finger depression  132  facilitates removal of the piece of glass  128  from the enlarged opening  94 . The first finger depression  132  can vary in size, shape and configuration but should be large enough to accommodate a person&#39;s index finger up to the first knuckle. Likewise, a second finger depression  134  is shown formed in the top wall  980 , adjacent to the enlarged opening  100 . The second finger depression  134  is again optional but serves a very useful purpose. The second finger depression  134  facilitates removal of the piece of glass  130  from the enlarged opening  100 . The second finger depression  130  can vary in size, shape and configuration but should be large enough to accommodate a person&#39;s index finger up to the first knuckle. 
     Referring again to  FIGS. 10 and 13 , one will notice that the baffle tank  22  has a rim  136  which surrounds the top wall  92  of the first chamber  88  and a rim  138  which surrounds the top wall  98  of the second chamber  90 . By “rim” it is meant a border, edge or margin of an object. The rims  136  and  138  function to create wells  140  and  142  in the top walls,  92  and  98  respectively. By “well” it is meant an enclosed space for receiving and holding something, such as water. The depth of each well  140  and  142  can vary. Desirably, each of the wells  140  and  142  has the same depth. Alternatively, the well  140  could have a different depth than the well  142 . Any incoming water that does not pass through the inlet  96  but instead splashes on the top wall  92  of the first chamber  88  can pool in the well  140 . This water would then be able to flow downward into first chamber  88  via the first finger depression  132 . Likewise, any water that would accumulate on the top wall  98  of the second chamber  90  can pool in the well  142 . This water would then be able to flow downward into second chamber  90  via the second finger depression  134 . 
     Referring again to  FIG. 2 , as explained above, the filter system  18  includes at least one return conduit  106  for routing clean, filtered fluid (water) back to the container holding a large quantity of fluid (the aquarium)  10 . 
     Referring again to  FIGS. 10-12 , one will notice that each of the sidewalls  84 ,  84 ,  84  and  84  has one or more structural members  150  to give it extra strength, integrity, rigidity and support. Optionally, at least one of the sidewalls  84  could have one or more structural members  150 . Each of the structural members  150  can vary in size, shape and configuration. The structural members  150  are depicted as having a trapezoid shape By “trapezoid” it is meant a quadrilateral having two parallel sides. Each structural member  150  is shown as being a large indentation formed in each of the sidewalls  84 ,  84 ,  84  and  84 . However, it should be understood that each of the structural members  150  could be made to protrude outward from one or more of the sidewalls  84  and provide the same structural support. Still another option is to form the structural members  150  into unique shapes resembling one or more ribs, trusses, diagonal support beams, or a honeycomb design. Still a further option is to make the sidewalls  84 ,  84 ,  84  and  84  thicker so that the structural members  150  are not needed. 
     The pair of slits or V-shaped grooves  122  and  124  is not shown having a structural member  150 . However, if needed, the sidewalls created by the V-shaped grooves  122  and  124  could also contain a structural member  150 . 
     Referring now to  FIG. 12 , the baffle tank  22  further includes first and second abutments  152  and  154  in the first chamber  88 . The first and second abutments,  152  and  154  respectively, can vary in size, shape and configuration. The abutments  152  and  154  can be molded into the baffle tank  22  as it is being formed. This means that the first and second abutments,  152  and  154  respectively, are integral with the baffle tank  22 . Alternatively, the first and second abutments,  152  and  154  respectively, could be formed after the baffle tank  22  is formed or molded. 
     The first abutment  152  is spaced apart from the second abutment  154 . The distance between the two abutments  152  and  154  can vary depending upon the size of the baffle tank  22 . For a baffle tank  22  having a width w of about 16 inches, the distance between the first and second abutments,  152  and  154  respectively, could be about 6 inches or more. Desirably, for a baffle tank  22  having a width of about 16 inches, the distance between the first and second abutments,  152  and  154  respectively, could be about 7 inches or more. More desirably, for a baffle tank  22  having a width of about 16 inches, the distance between the first and second abutments,  152  and  154  respectively, could be at least about 8 inches. 
     Referring now to  FIG. 11  when the abutments  152  and  154  are molded simultaneously with the baffle tank  22 , a pair of recesses  156  and  158  can be created in the exterior, bottom wall  82  of the baffle tank  22 . The recesses  156  and  158  decrease the amount of material that is needed to form the first and second abutments,  152  and  154  respectively. By forming the first and second abutments,  152  and  154  respectively, as hollow members, one can decrease the overall weight of the baffle tank  22 . 
     Alternatively, the first and second abutments,  152  and  154  respectively, could be separate members that are affixed or secured to the interior of the bottom wall  82  after the baffle tank  22  is formed. 
     Referring again to  FIG. 12 , the first and second abutments,  152  and  154  respectively, are optional members that do not have to be present. The first and second abutments,  152  and  154  respectively, can vary in size, shape and configuration. In addition, one could utilize more than the two abutments  152  and  154 , if needed. The first and second abutments,  152  and  154  respectively, can be of equal size or be of a different size. In  FIG. 12 , the first abutment  152  is shown to having a length l 2  and a width w 2 . The length l 2  is aligned parallel to the longitudinal central axis X 1 -X 1  of the baffle tank  22  and the width w 2  is aligned parallel to the transverse central axis Z 1 -Z 1  of the baffle tank  22 . Other arrangements are also possible. The length l 2  and the width w 2  of the first abutment  152  can vary. The length l 2  of the first abutment  152  can range from about 4 inches to about 7 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the length l 2  of the first abutment  152  is from between about 5 inches to about 6 inches. More desirably, the length l 2  of the first abutment  152  is about 5.5 inches. The width w 2  of the first abutment  152  can range from between about 1 inch to about 3 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the width w 2  of the first abutment  152  is about 2 inches. 
     Still referring to  FIG. 12 , a shoulder  160  is formed on the top of the first abutment  152 , adjacent to the end located farthest away from the sidewall  84 . The shoulder  160  can span across the width w 2  of the first abutment  152  and have a length of about 1 inch measured parallel to the length l 2  of the first abutment  152 . The second abutment  154  is shown to having a length l 3  and a width w 3 . The length l 3  is aligned parallel to the longitudinal central axis X 1 -X 1  of the baffle tank  22  and the width w 3  is aligned parallel to the transverse central axis Z 1 -Z 1  of the baffle tank  22 . Other arrangements are also possible. The length l 3  and the width w 3  of the second abutment  154  can vary. The length l 3  of the second abutment  154  can range from about 4 inches to about 7 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the length l 3  of the second abutment  154  is from between about 5 inches to about 6 inches. More desirably, the length l 3  of the second abutment  154  is about 5.5 inches. The width w 3  of the second abutment  154  can range from between about 1 inch to about 4 inches when the baffle tank  22  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the width w 3  of the second abutment  154  is about 3 inches. One will notice that the second abutment  154  is wider than the first abutment  152 . The purpose for this will be explained shortly. An L-shaped shoulder  162  is formed on the top of the second abutment  154 . The L-shaped shoulder  162  can extend across the length l 3  and the width w 3  of the second abutment  154 . The thickness of the L-shaped shoulder  162  can be about 1 inch or less. 
     Referring now to  FIGS. 17 and 18 , the first and second abutments,  152  and  154  respectively, function as support for at least one basket  164 . When two or more baskets  164 ,  164  are present, they can be stacked vertically, one on top on another in a nesting relationship. One, two, three, four, five, six or more basket(s)  164  can be utilized depending upon their size, shape and configuration, and the overall height of the baffle tank  22 . A rectangular basket  164  is shown in  FIGS. 17 and 18  although the basket(s)  164  can vary in size, shape and configuration. The basket(s)  164  can be constructed from various materials. Plastic is a good material from which to construct the basket(s)  164  because plastic is easily molded, is relatively inexpensive, is light weight, and will not rust or corrode when immersed in water. 
     The basket  164  has a length l 4 , a width w 4  and a height h 4 , all of which can vary. The length l 4  can range from between about 6 inches to about 20 inches depending on the size of the baffle tank  22 . A length l 4  of from between about 9 inches to about 12 inches works well for a baffle tank  22  having a width of about 16 inches. The width w 4  can range from between about 3 inches to about 6 inches depending on the size of the baffle tank  22 . A width w 4  of from between about 4 inches to about 5 inches works well for a basket  164  having a length l 4  of less than about 12 inches. The height h 4  can range from between about 1.5 inches to about 4 inches depending on the size of the baffle tank  22 . A height h 4  of from between about 2 inches to about 3 inches works well for a basket  164  having a length l 4  of less than about 12 inches. 
     Still referring to  FIGS. 17 and 18 , the basket  164  has an upper lip  166  that extends completely around it outer perimeter. The width and thickness of the lip  166  can vary. A width of about 0.25 inches or less and a thickness of about 0.125 inches or less, works well. The basket  164  also has a bottom  168  with multiple openings  170  formed therethrough. The openings  170  can vary in size and shape. Desirably, all of the openings  170  are of the same size or diameter. The openings  170  are shown in  FIG. 18  as square openings, although they could be circular. The openings  170  can be formed by various ways known to those skilled in the art. The openings  170  can be formed when the basket  164  is molded. Alternatively, the four sidewalls of the basket  164  could be formed and then a screen (not shown) could be attached to the sidewalls to form a perforated bottom  168 . 
     The basket  164  is sized, shaped and configured to span across the pair of first and second abutments,  152  and  154  respectively. The shoulder  160  formed on the first abutment  152  and the L-shaped shoulder  162  formed on the second abutment  154  serve to hold the lower most basket  164  stationary so that it will not move as water is introduced into the first chamber  88 . The nesting relationship between two or more vertically stacked baskets  164 ,  164  will cause all of the baskets  164 ,  164  to remain stationary. 
     Each basket  164  will hold a plurality of small, high surface area members, such as ceramic spherical balls, that will create a bacteria culture for biological filtration in the first chamber  88 . The high surface area members are sometimes referred to as the biological filtration medium. 
     Optionally, an open cell foam member (not shown) and/or a perforated plate (not shown) can be placed in the upper most basket  164  to help prevent debris and other refuse from contacting the ceramic balls retained in the one or more baskets  164 . A stack of two or more baskets  164 ,  164  is referred to as a media stack or a biological filtration stack by those in the filtering business. 
     Referring again to  FIG. 10 , the baffle tank  22  can optionally include at least one pre-formed pilot dimple  172 . The pre-formed pilot dimples  172  serve as measured locations where openings can be drilled or created into the baffle tank  22  such that connecting hoses can be attached in a horizontal alignment between the baffle tank  22  and another tank, for example, the reservoir tank  24 , in the filter system  18 . With connecting hoses between adjacent tanks, sometimes it is critical that a hose be attached on the same horizontal plane between the two tanks. The pre-formed pilot dimples  172  provide an easy and convenient way for this to be accomplished. The pre-formed pilot dimples  172  can be formed anywhere in the exterior surface of the baffle tank  22 . Desirably, the pre-formed pilot dimples  172  are formed in one or more of the sidewalls  84 ,  84 ,  84  and  84 . 
     In  FIG. 10 , three pre-formed pilot dimples  172 ,  172  and  172  are shown formed in each of the sidewalls  84 ,  84 ,  84  and  84 . Each of the pre-formed pilot dimples  172  facilitates drilling or forming a larger size opening in the baffle tank  22 . The pre-formed pilot dimples  172  can be molded into the baffle tank  22  when it is being molded or the pre-formed pilot dimples  172  can be bored into the sidewall  84 ,  84 ,  84  and  84  or into the top walls  92  and  98  after the baffle tank  22  has been formed. Each of the pre-formed pilot dimples  172  has a diameter of about 0.25 inches or less Desirably, each of the pre-formed pilot dimples  172  has a diameter of about 0.2 inches or less. The depth of each of the pre-formed pilot dimples  172  can vary. A depth of less than about 0.3 inches for each pre-formed pilot dimple  172  is sufficient when the thickness of the sidewalls  84 ,  84 ,  84  and  84  and the top walls  92  and  98  of the baffle tank  22  are less than about 1 inch. 
     Referring now to  FIGS. 2, 19 and 20 , the filter system  18  may optionally include a reservoir tank  24 . The reservoir tank  24  can be used to compliment the sock tank  20  and the baffle tank  22 . Alternatively, the reservoir tank  24  can be used as an evaporation tank, a stand-alone sump, a feeder fish tank, a refugium, or simply as a reservoir for water that can be added to the aquarium  10 . By “refugium” it is meant an area that has escaped ecological changes occurring elsewhere and so provides a suitable habitat for relict species. 
     The size, shape and configuration of the reservoir tank  24  can vary. The reservoir tank  24  can be an integral member. By “integral” it is meant a complete unit, a whole. The reservoir tank  24  can be constructed in any manner known to those skilled in the art. For example, the reservoir tank  24  can be molded as an integral member, can be assembled from individual parts, be cast, be carved from a single member, etc. Desirably, the reservoir tank  24  is molded using various molding techniques well known to those skilled in the molding arts. When molded, the reservoir tank  24  will exhibit a one piece design with no seams, joins or welds. This is advantageous for it eliminates the possibility of having fluid leak out of the reservoir tank  24 . A molding apparatus that works well in molding the reservoir tank  24  is a rotational mold. 
     The reservoir tank  24  can be formed, molded or machined from any of the materials mentioned above with reference to the sock tank  20  and/or the baffle tank  22 . Generally, the reservoir tank  24  will be molded from the same material used to mold the sock tank  20  and the baffle tank  22 . Desirably, the reservoir tank  24  is molded from High Density Polyethylene (HDPE), High Density Polypropylene (HDPP), Low density Polyethylene (LDPE) or Low Density Polypropylene (LDPP). Other high or low density thermoplastics could also be used. 
     Still referring to  FIGS. 19 and 20 , the reservoir tank  24  has a top wall  174 , a bottom wall  176  and at least one sidewall  178  joining the top wall  174  to the bottom wall  176  to form an enclosure  180 . Four sidewalls  178 ,  178 ,  178  and  178  are shown giving the reservoir tank  24  a rectangular configuration. Any number of sidewalls  178  can be used. A single sidewall  178  would produce a circular enclosure  180 , such as a cylinder. The bottom wall  176  can be secured to the at least one sidewall  178  in any manner known to those skilled in the art provided a water proof seal is formed. By “waterproof seal” it is meant impervious to or unaffected by water. Molding the reservoir tank  24  is most desirable. However, the bottom wall  176  could be secured to the at least one sidewall  178  using glue, an adhesive, a co-adhesive, a heat bond, a pressure bond, a heat and pressure bond, a weld, etc., or a combination of two or more of the aforementioned bonding techniques. 
     Referring to  FIG. 19 , the reservoir tank  24  has a longitudinal central axis X 2 -X 2 , a vertical central axis Y 2 -Y 2 , and a transverse central axis Z 2 -Z 2 . The reservoir tank  24  also has a length l 5 , a width w 5  and a height h 5 . The length l 5 , the width w 5  and the height h 5  of the reservoir tank  24  can vary in dimension. The length l 5  can range from between about 18 inches to about 40 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . A length l 5  of less than about 30 inches works well when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the length l 5  is about 25 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . The width w 5  can range from between about 10 inches to about 30 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . A width w 5  of less than about 25 inches works well when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the width w 5  is about 20 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . The height h 5  can range from between about 10 inches to about 40 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the height h 5  can range from between about 12 to about 30 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the height h 5  can range from between about 15 to about 25 inches when the reservoir tank  24  is used as part, of the filter system  18  for a fish aquarium  10 . Even more desirably, the height h 5  can range from between about 16 to about 22 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . It is advantageous to form the reservoir tank  24  such that it has a height h 5  approximately equal to the height h 1  of the baffle tank  22 . 
     Still referring to  FIGS. 19 and 20 , the reservoir tank  24  also has an enlarged opening  182  formed therein. The enlarged opening  182  can vary in size, shape and configuration. The enlarged opening  182  is depicted as a rectangular opening although any shape is possible. As shown in  FIG. 20 , the enlarged opening  182  has a length l 5  and a width w 6 . The length l 6  of the enlarged opening  182  can range from between about 6 inches to about 25 inches. Desirably, the length l 6  of the enlarged opening  182  is at least about 10 inches. More desirably, the length l 6  of the enlarged opening  182  is about 15 inches. Even more desirably, the length l 6  of the enlarged opening  182  is about 16 inches. The width w 6  of the enlarged opening  182  can range from between about 5 inches to about 25 inches. Desirably, the width w 6  of the enlarged opening  182  is at least about 6 inches. More desirably, the width w 6  of the enlarged opening  182  is about 8 inches. Even more desirably, the width w 6  of the enlarged opening  182  is about 10 inches. 
     Referring to  FIG. 21 , a piece of glass  184  is sized and shaped to cover the enlarged opening  182 . The piece of glass  184  is removable by lifting it upward and away from the enlarged opening  182 . One could use a different material other than glass, if one so desired. However, glass is a very common material that is relatively inexpensive, is resilient to water, comes in different thicknesses, can be cut into various shapes, has a certain weight to it so that it will remain in place on the top wall  174 , and is washable should it get dirty. 
     The primary function of the piece of glass  4  is to slow down, limit or prevent evaporation of water from the reservoir tank  24 . 
     The thickness of the piece of glass  184  can vary. When the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 , the thickness of the piece of glass  184  can range from between about 0.1 inches to about 0.5 inches. Desirably, the thickness of the piece of glass  184  can range from between about 0.2 inches to about 0.4 inches. More desirably, the thickness of the piece of glass  184  can be about 0.375 inches. 
     Referring again to  FIGS. 19 and 20 , the reservoir tank  24  a first finger depression  186  and a second finger depression  188  are shown formed in the top wall  174 , adjacent to the enlarged opening  182 . The first and second finger depressions,  186  and  188  respectively, are optional but they serve a very useful purpose. The first and second finger depressions,  186  and  188  respectively, facilitates removal of the piece of glass  184  from the enlarged opening  182 . The first and second finger depressions,  186  and  188  respectively, can be spaced apart from one another by at least about 10 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . Desirably, the first and second finger depressions  186  and  188  respectively, are spaced apart from one another by at least about 12 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . More desirably, the first and second finger depressions  186  and  188  respectively, are spaced apart from one another by at least about 15 inches when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . The first and second finger depressions  186  and  188  respectively, can vary in size, shape and configuration but should be large enough to accommodate a person&#39;s index finger up to the first knuckle. Alternatively, a single finger depression could be used. 
     Still referring to  FIGS. 19 and 20 , one will notice that the reservoir tank  24  has a rim  190  which surrounds the top wall  174 . By “rim” it is meant a border, edge or margin of an object. The rim  190  functions to create a well  192  in the top wall  174 . By “well” it is meant an enclosed space for receiving and holding something, such as water. The depth of the well  192  can vary. Desirably, the well  192  has a depth of less than about 1 inch when the reservoir tank  24  is used as part of the filter system  18  for a fish aquarium  10 . The piece of glass  184  can be positioned in the well  192 . Any water that is accidentally deposited on the top wall  174  of the reservoir tank  24  can pool in the well  192 . This water would then be able to flow downward into the reservoir tank  24  via the first and/or second finger depressions  186  and/or  188  respectively. 
     Referring now to  FIGS. 2 and 22 , a second fluid connector  194  is shown which fluidly connects the baffle tank  22  and the reservoir tank  24 . The reservoir tank  24  is capable of holding a larger volume of fluid that the second chamber  88  of the baffle tank  22 . The second fluid connector  194  has a first end  196  and a second end  198 . The first end  196  is attached to the at least one sidewall  84  of the baffle tank  22  at a location below the upper level of the fluid (water) in the second chamber  90 . The second end  198  of the second fluid connector  194  is secured to the at least one sidewall  178  of the reservoir tank  24  at a location below the upper level of the fluid (water) in reservoir tank  24 . The second fluid connector  194  is horizontally aligned such that the first and second ends,  196  and  198  respectively, reside in the same horizontal plane. This setup will ensure that the fluid level in both the baffle tank  22  and in the reservoir tank  24  are at the same height even though the actual fluid level can move up or down. 
     It should be noted that the first and second ends,  196  and  198  respectively, can attach to opening or holes that were formed where the pilot dimples  172 ,  172  were located. The pilot dimples  172 ,  172  can be very accurately positioned in the baffle tank  22  and in the reservoir tank  24  when the tanks,  22  and  24  were manufactured. The pre-formed, pilot holes  172 ,  172  thus ensure that the second fluid connector  194  is horizontally aligned between the two tanks  22  and  24 . 
     Referring now to  FIG. 23 , a side view of a filter system  18 ′ is shown which includes a sock tank  20 , a baffle tank  22  and a reservoir tank  24  is depicted with the baffle tank  22  and the reservoir tank  24  being fluidly connected together by the second fluid connector  194 . The first end  196  of the second fluid connector  194  is attached to the at least one sidewall  84  of the baffle tank  22  at a location equal to the upper end  120  of the second baffle  118 . This location is at the upper level of the fluid (water) in the second chamber  90 . The second end  198  of the second fluid connector  194  is secured to the at least one sidewall  178  of the reservoir tank  24  at a location equal to the upper end  120  of the second baffle  118 . This location is at the upper level of the fluid (water) in the second chamber  90 . This means that the reservoir tank  24  can serve as a refugium or as a holding tank for small fish because the fluid (water) level in the reservoir tank  24  will not substantially decrease. The small fish can be used as a food source for the aquarium  10  where larger fish need fresh, live fish as food. The second fluid connector  194  is horizontally aligned such that the first and second ends,  196  and  198  respectively, reside in the same horizontal plane. However, in  FIG. 23 , the second fluid connector  194  is positioned at an elevated height compared to its location in  FIG. 22 . 
     Referring to  FIG. 24 , a side view of a filter system  18 ″ is shown which includes a sock tank  20 , a baffle tank  22 , and first and second reservoir tanks,  24  and  25  respectively. Each of the reservoir tanks  24  and  25  has a top wall  174 , a bottom wall  176  and at least one sidewall  178  connecting the top wall  174  to the bottom wall  176  to form an enclosure  180 . Each of the first and second reservoir tanks  24  and  25  respectively, is capable of holding a larger volume of fluid that the second chamber  88  of the baffle tank  22 . The filter system  18 ″ has a second fluid connector  194  secured at the same location as is shown in  FIG. 22 . In addition, the filter system  18 ″ further includes a third fluid connector  200 . The third fluid connector  200  has a first end  202  and a second end  204 . The first end  202  is attached to the at least one sidewall  178  of the first reservoir tank  24  at a location below the upper level of the fluid (water) in the second chamber  88  of the baffle tank  22 . The second end  204  of the third fluid connector  200  is secured to the at least one sidewall  178  of the second reservoir tank  25  at a location below the upper level of the fluid (water) in second chamber  90  of the baffle tank  22 . The third fluid connector  200  is horizontally aligned such that the first and second ends,  202  and  204  respectively, reside in the same horizontal plane. In addition, the third fluid connector  200  is aligned in the same horizontal plane as the second fluid connector  194 . This setup will ensure that the fluid level in the baffle tank  22  and in the first and second reservoir tanks,  24  and  25  respectively, will be at the same height even though the actual fluid level in all three tanks  22 ,  24  and  25  can move up or down. 
     It should be noted that the first and second ends,  202  and  204  respectively, of the third fluid connector  200  can be attach to opening or holes that are formed where the pilot dimples  172 ,  172  were located. The pilot dimples  172 ,  172  can be very accurately positioned in the baffle tank  22  and in the first and second reservoir tanks,  24  and  25  respectively, when the tanks  22 ,  24  and  25  were manufactured. The pre-formed, pilot holes  172 ,  172  thus ensure that the second fluid connector  194  and the third fluid connector  200  will be horizontally aligned between the three tanks  22 ,  24  and  25 . 
     Referring to  FIG. 25 , a sideview of another filter system  18 ′″ is shown which includes a sock tank  20 , a baffle tank  22 , and first and second reservoir tanks,  24  and  25  respectively. Each of the reservoir tanks  24  and  25  has a top wall  174 , a bottom wall  176  and at least one sidewall  178  connecting the top wall  174  to the bottom wall  176  to form an enclosure  180 . Each of the first and second reservoir tanks  24  and  25  respectively, is capable of holding a larger volume of fluid that the second chamber  88  of the baffle tank  22 . The filter system  18 ″ in  FIG. 25  differs from that shown in  FIG. 24  in that the second and third fluid connectors,  24  and  25  respectively, are located at an elevated height compared to their locations in  FIG. 23 . Again, the second and third fluid connectors  194  and  200  are horizontally aligned with one another. In the filter system  18 ′″, both of the first and second reservoir tanks,  24  and  25  respectively, can serve as refugiums or as holding tanks for small fish because the fluid (water) level in the reservoir tanks  24  and  25  will not substantially decrease. The small fish can be used as a food source for the aquarium  10  where larger fish need fresh, live fish as food. 
     While the invention has been described in conjunction with several specific embodiments, it is to be understood that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, this invention is intended to embrace all such alternatives, modifications and variations which fall within the spirit and scope of the appended claims.