Abstract:
An aquarium filtering and purifying system includes an upper display tank and a lower filter tank. The water from the upper tank can be delivered to the lower tank to a filter, such as within a surrounding filter fabric or membrane, such as a filter sock. An air tube can also be inserted into the filter tank to an unfiltered side of the filter, such as within the filter sock, to deliver air bubbles into the filter tank. The air tube can have an air stone at the end thereof to diffuse the air bubbles. Further air stones can be provided on an outside of the sock in the first compartment. Filtered water is delivered to a second compartment in the filter tank. The next compartment can have sand, and/or rocks and/or algae and/or a clean-up crew to assist in purifying the water. Water from the second compartment then passes to a third compartment, through a bubble trap, and then is pumped back to the display tank. Alternatively, the first compartment can be provided with a macro algae bed instead of a filter sock.

Description:
BACKGROUND 
       [0001]    The present invention is directed to aquarium systems used to display marine life. Aquariums and filtering systems for keeping and displaying marine life are known. In order to keep marine life healthy the water must be filtered and proteins and impurities removed. 
         [0002]    A particular problem with most aquarium systems is the removal of harmful proteins and other impurities that are continuously produced by marine life in the aquarium. Filters must remove the proteins, amino acids, fatty acids and other proteinaceous material which accumulate and are concentrated in the water contained in the aquarium tank. Decaying food and fish feces produce ammonia and other nitrogen compounds which can be poisonous to the aquatic animals if allowed to accumulate in the aquarium. 
         [0003]    Generally, conventional filtration and aeration systems usually involve the continuous flow of water between the aquarium tank and a filter. Sometimes the filter is mounted on the exterior side of one of the aquarium tank walls. Also, two tank systems are known wherein an upper tank serves as the display tank and a lower tank serves as a filter tank. 
         [0004]    U.S. Pat. No. 5,084,164 describes a filter assembly having an upper tank and a lower tank. Water from the upper tank flows below to pass through a filter in the lower tank. A fraction of that water passes into a chamber that is fed air bubbles from below using an air stone to remove foam into a side container. 
         [0005]    U.S. Pat. No. 3,971,338 describes a filter assembly having an upper tank and lower compartments. Water from the upper tank flows through filter material in the bottom of the tank to a recirculation pump. Additionally, water from an upper portion of the tank flows into an air compartment that is fed air bubbles from an air stone to create foam to be removed. Water at the bottom of this air compartment, along with the filtered water from the bottom of the tank can be passed through a chemical filter and then recirculated back to the tank by a pump. 
         [0006]    U.S. Pat. No. 5,054,424 describes an upper tank/lower tank system. Water passes through a filter from the upper tank to the lower tank. Within the lower tank is an aeration section that uses an air pump and an air stone to inject oxygen into the water. 
         [0007]    The present inventor has recognized a need for an effective aquarium filtering and purifying system for aquariums. The present inventor has recognized a need to create a filtering and purifying system for aquariums wherein equilibrium between the animals, plants, and bacteria can be maintained for extended periods of time. The present inventor has recognized a need to provide a simplified filtering and purifying aquarium system for the home at low cost, particularly suited for sea water aquariums. 
         [0008]    The present inventor has recognized a need to provide a filtering and purifying aquarium system that is simple to operate and maintain. The present inventor has recognized a need to provide a filtering and purifying aquarium system that may easily be added to existing home aquariums. 
       SUMMARY 
       [0009]    An exemplary embodiment of the invention comprises an aquarium filtering and purifying system that includes an upper display tank and a lower filter tank. The water from the upper tank can be delivered to the lower tank to a filter, such as within a surrounding filter fabric or membrane, such as a filter sock. An air tube can also be inserted into the filter tank to an unfiltered side of the filter, such as within the filter sock, to deliver air bubbles into the filter tank. The air tube can have an air stone at the end thereof to diffuse the air bubbles. Filtered water is delivered to a second compartment in the filter tank. The next compartment can have sand, and/or rocks and/or algae and/or a “clean-up crew” to assist in purifying the water. A clean-up crew typically includes snails, crabs, shrimps, and/or starfish that clean up non-living organic matter and keep algae under control. 
         [0010]    Water from the second compartment then passes to a third compartment, through a bubble trap, and then is pumped back to the display tank. 
         [0011]    Alternatively, the first compartment can be provided with a macro algae bed instead of a filter sock. 
         [0012]    The system is particularly advantageous for filtering and purifying sea water aquariums. For a new display tank, the tank must be “cycled” to produce a livable environment with a proper level of useful bacteria. The system allows for a decreased cycle time for fish to be placed in a new display tank, allowing a proper livable environment for a sea water tank in as little as three days. The system allows for the elimination of the need for water changes. The only step needed is to top off evaporated water every few days. The normal salinity for a sea water tank is 1.024 (specific gravity). The system can maintain low hypo-salinity (1.008 specific gravity) if needed for treating parasitic infestation, for an extended period of time, for 4 months or longer, without the need for water changes, or additives added to maintain a livable environment. Added water is typically reverse osmosis deionized (“RO DI”) water. 
         [0013]    Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a schematic diagram of the aquarium system of the present invention; 
           [0015]      FIG. 2  is a sectional view of a filter tank taken from  FIG. 1 ; 
           [0016]      FIG. 3  is an enlarged perspective view taken from  FIG. 1 ; and 
           [0017]      FIG. 4  is a schematic diagram of an alternate aquarium system of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated. 
         [0019]      FIG. 1  illustrates an aquarium system  10  according to the present invention. The system includes a display tank  20  supported above a filter tank  30 . The tanks have end walls, sidewalls and a bottom wall that can be composed of transparent glass or acrylic material. The display tank can have fish and other marine life, and rocks, sand, algae and clean-up crew. The display tank can include one or more wave-making devices  22 . A tank filter tube  36  has an inlet  38  at and slightly below a water line  40  in the display tank  20 . The filter tube delivers water into the filter tank  30 . Water from the filter tank  30  is pumped from a water pump  46  through a recirculation tube  50  back to the display tank  20 , with the end of the tube  50  being about one inch or so below the water level  40 . 
         [0020]      FIG. 3  illustrates the inlet  38  in more detail. The filter tube terminates in a  90  degree elbow  38   a,  facing upward. A short pipe nipple  38   b  connects the elbow  38   a  to a cap  38   c,  by threading or gluing to the cap and by press fitting into the elbow. The cap  38   c  and nipple  38   b  have vertical slots  38   d  cut through sidewalls thereof and through the cap end wall which are spaced apart around the circumference of the cap and nipple to allow water to pass into the elbow  38   a  and into the filter tube  36 , but prevents fish from inadvertently entering the cap  38   c  and nipple  38   b  and then entering the elbow  38   a.  The cap  38   c  and the nipple  38   b  form a grate or screen for water entry into the inlet  38 . The filter tube  36  extends from the elbow  38   a  through a side of the display tank  20  by use of a seal  37  as is known. 
         [0021]    The water level  40  is maintained at a height wherein the upward end of the elbow  38   a  is at about a 1 inch depth and the top wall of the cap  38   c  is above the water level  40 . Effectively, the inlet  38  can skim the water surface at the water level  40 . 
         [0022]    Water from the filter tube  36  is fed into a first compartment  54  of the filter tank  30 . The filter tube  36  delivers water through an open end  58  that is submerged within a filter sleeve or sock  64 . The sock  64  is held upright at a desired elevation by use of one or more clamps  65  hung by wire from external structure. Water within the first compartments  54  spills over a baffle  68  and into a second compartment  70 . Water within the second compartment  70  spills over a baffle  72 , passes under a baffle  74  and spills over a baffle  76  into a third compartment  84 . 
         [0023]    The filter tank can be provided with one or more lamps  85  for radiating light onto the tank and one or more heaters  86 ,  87  for heating the water in the filter tank to a desired temperature appropriate for sustaining life in both tanks. 
         [0024]    The pump  46  pumps water from the third compartment  84  through the recirculation tube  50  back into the display tank  20 . The tube  50  passes through a wall of the tank through a seal  89  and has an outlet  51  about an inch or so below the surface  40 . 
         [0025]    An air pump  90  delivers pressurized air through an air feed tube  94  into the first compartments  54  and within the filter sock  64 . An end of the tube  94  is connected to one or more air stones  98  which defuse the pressurized air into bubbles to aid in aeration of the water within the filter sock  64  and within the first compartments  54 . Another air tube  93  can deliver air from the pump  90  to one or more air stones  95  within the first compartment on an outside of the sock  64 . The air stones  95  provide air bubble induced turbulence in the first compartment to help move waste passing through the filter into the second compartment to feed algae and clean-up crew within the second compartment. In one embodiment there are two air stones  98  and six air stones  95 . 
         [0026]    The operation of the air stone  98  generating fine air bubbles causes protein within the water to foam within the filter sock at the water line and below. This foam is contained within the filter sock. When the sock fills with foam and waste from the display tank, the sock can be removed and replaced with a clean sock, either a new sock or a cleaned sock. A bed of rocks  108  and/or macro algae  110  and/or a clean-up crew  111  can be contained in the second compartment for the purpose of purifying the water before return of the water to the display tank  20 . 
         [0027]      FIG. 2  illustrates the filter tank  30  in more detail. The filter tank is a rectangular fish aquarium tank having a bottom  116 , sides  118 ,  120 , a front wall (not shown) and a back wall  126 . The top can be open. The baffles  68 ,  72 ,  76  are walls that extend between the front wall and the back wall, perpendicularly and are effectively sealed to the front wall and the back wall. The baffles  68 ,  72 ,  76  are sealed to the bottom  116  and extend vertically from the bottom  116 . The baffle  74  is a wall that extends between the front wall and the back wall perpendicularly and is sealed to the front wall and back wall. The baffle is spaced from the bottom to allow water to flow beneath the baffle  74 . 
         [0028]    In the illustrated embodiment the filter tank has a lengthwise dimension a, a height dimension b, and a depth dimension (into the page). The first compartments  54  as a length c. The baffle  68  as a height d. The second compartment  70  as a length e. The baffle  72  as a height f. The baffle  74  has a height l above the top of the baffles  72 ,  76  and a height h below a top of the baffles  72 ,  76 . The baffle  76  has a height j. The baffle  74  can be located in a lengthwise direction equally spaced between the two baffles  72 ,  76  and the two baffle  72 ,  76  are separated by a length g. The third compartment has a length k. The baffles  72 ,  74 ,  76  form a “bubble trap” to prevent air bubbles from reaching the water pump  46 . 
         [0029]    For one size tank, an exemplary depth dimension (into the page) is 12 inches. The corresponding other dimensions (in inches) are exemplary: a=48; b=20; c=13; d=11; e=21; f=9; g=4; h=7; i=5; j=9; k=10. 
         [0030]    Because of the baffles and the control of the pump, water in the filter tank maintains a highest water level  54   a  in the first compartment, an intermediate water level  70   a  in the second compartment, and a lowest water level  84   a  in the third compartment. 
         [0031]    Water enters the first compartment  54  from the display tank  20  below the water tube  40 . Multiple fine bubble air stones  98  can be placed in compartment  54  all connected to the air tube  94  to deliver air bubbles into the compartment  54 . The air stones  98  can be placed in the filter sock  64  or the compartment  54  can be instead contain or be filled with macro algae. Water flows from compartment  54  to the compartment  70  over a small waterfall formed by baffle  68 . Compartment  70  can contain or be filled with a sand bed, and/or live rock, and/or macro algae and/or a clean-up crew. 
         [0032]    Water enters compartment  84  from the three panel bubble trap  72 ,  74 ,  76 . The trap can be configured to operate with the water level approximately 1 inch higher than a top elevation of the panels  72 ,  76 . This eliminates turbulence in compartment  84 . Water in compartment  84  returns to display tank via the submersible pump  46  and the recirculation tube  50 . 
         [0033]    The exemplary dimensions listed above for the tank  30  are consistent with a  55  gallon tank. This size tank is effective for a 125 gallon display tank  20 . Advantageously the filter tank has sufficient volume such that upon loss of power, draining of water from the display tank  20  does not overflow the filter tank  30 . 
         [0034]      FIG. 4  illustrates a larger display tank  20 ′ and a larger filter tank  30 ′. These tanks operate in like fashion to the tanks disclosed in  FIGS. 1-3  with the same reference numbers used to describe identical elements. The filter tank is mirror image identical across the plane identified as P-P. The duplicated elements on the right side of P-P are indicated by the same reference number with a prime punctuation. As an example, the pump  46 ′ delivering water through the tube  50 ′ through a seal  89 ′ into the tank  20 ′ through an outlet  51 ′ is a duplicate of the pump  46  delivering water through the tube  50  through the seal  89  into the tank  20 ′. According to this embodiment the left side of P-P operated as described in the embodiment disclosed in  FIGS. 1-3 . 
         [0035]    According to this embodiment of  FIG. 4 , on the right side of P-P, water from the filter tube  36 ′ is fed into a fourth compartment  54 ′ of the filter tank  30 ′. The filter tube  36 ′ delivers water through an open end  58 ′ that is submerged within a filter sleeve or sock  64 ′. The sock  64 ′ is held upright at a desired elevation by use of one or more clamps  65  hung by wire from external structure as shown on the left side of the filter tank. Water within the fourth compartments  54 ′ spills over a baffle  68 ′ and into a fifth compartment  70 ′. Water within the fifth compartment  70 ′ spills over a baffle  72 ′, passes under a baffle  74 ′ and spills over a baffle  76 ′ into the third compartment  84 . 
         [0036]    The filter tank  20 ′ can be provided with one or more heaters  86 ′,  87 ′ for heating the water in the filter tank to a desired temperature appropriate for sustaining life in both tanks. 
         [0037]    The pump  46 ′ pumps water from the third compartment  84  through the recirculation tube  50 ′ back into the display tank  20 ′. The tube  50  and the tube  50 ′ pass through a back wall of the tank  20 ′ through the seal  89  and a seal  89 . The tubes  50  and  50 ′ each has a respective outlet  51 ,  51 ′ facing in opposite directions about an inch or so below the surface  40 . 
         [0038]    An air pump  90 ′ delivers pressurized air through an air feed tube  94 ′ into the fourth compartment  54 ′ and within the filter sock  64 ′. An end of the tube  94 ′ is connected to one or more air stones  98 ′ which defuse the pressurized air into bubbles to aid in aeration of the water within the filter sock  64 ′ and within the fourth compartments  54 ′. Another air tube  93 ′ can deliver air from the pump  90 ′ to one or more air stones  95 ′ within the fourth compartment on an outside of the sock  64 ′. The air stones  95 ′ provide air bubble induced turbulence in the fourth compartment to help move waste passing through the filter into the fifth compartment to feed algae and clean-up crew within the fifth compartment. In one embodiment there are two air stones  98 ′ and six air stones  95 ′. 
         [0039]    The operation of the air stone  98 ′ generating fine air bubbles causes protein within the water to foam within the filter sock at the water line and below. This foam is contained within the filter sock. When the sock fills with foam and waste from the display tank, the sock can be removed and replaced with a clean sock, either a new sock or a cleaned sock. A bed of rocks  108 ′ and/or macro algae  110 ′ and/or a clean-up crew  111 ′ can be contained in the fifth compartment for the purpose of purifying the water before return of the water to the display tank  20 ′. 
         [0040]    According to the embodiment of  FIG. 4 , water in the display tank  20 ′ flows from a central region toward opposite ends to the outlets  38 ,  38 ′. The water enters the filter tank  30 ′ at opposite ends into the first and fourth compartments  54 ,  54 ′ respectively. Water then flows toward the center of the filter tank, over the baffles  68 ,  68 ′, then over the baffles  72 ,  72 ′, then under the baffles  74 ,  74 ′ and then over the baffles  76 ,  76 ′ into the central third compartment  84  where two pumps  46 ,  46 ′ return the water to the display tank  20 ′. Although two pumps  46 ,  46 ′ are shown it is possible that a single pump is used. Although two air pumps  90 ,  90 ′ are shown, it is possible that a single air pump is used to supply the air stones in both the first and fourth compartments. 
         [0041]    From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred.