Abstract:
An aquarium suitable for displaying jellyfish includes a chamber having interior walls that divide the chamber into a series of compartments. The first compartment is the viewing area having openings in the side walls that permit water to flow out of the viewing area while retaining jellyfish and flow into viewing area in a manner that keeps jellyfish suspended. A spillover riser is located between the first and second compartment that defines a channel through which the first and second compartment communicate. The second compartment has an air inlet providing the motive force to circulate water throughout the aquarium and introduce air bubbles to operate a foam fractionating device the inside the aquarium. The third compartment provides an area for placement of filter media and other necessary devices to keep jellyfish alive. The channel below the viewing area provides communication between the second and third compartment.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a Continuation in Part of currently pending U.S. application Ser. No. 13/739,553 which was filed on Jan. 11, 2013, which gets its priority date from provisional application U.S. 61/585,675 which was filed on Jan. 12, 2012. 
     
    
     FIELD OF THE INVENTION 
       [0002]    Aquariums for jellyfish. 
       BACKGROUND OF THE INVENTION 
       [0003]    The present invention relates to aquariums, typically of a size that would be used in a residence or business rather than a commercial aquarium, and that are intended to provide an appropriate environment, potentially including salt water, in which small jellyfish and similar organisms can survive for extended periods. 
         [0004]    The growth in the number and sophistication of municipal and state aquariums is at least one factor in the increased interest in smaller saltwater aquariums; e.g. for personal or business use rather than as public facilities. In turn, jellyfish represent a species that has gained interest because of their motion, appearance, and somewhat exotic nature. 
         [0005]    Jellyfish are, however, delicate creatures of which only a very small amount (typically about 5%) is solid organic matter. Jellyfish are technically a form of plankton, are invertebrates, and lack any brain or specialized systems of digestion or circulation. Jellyfish have a limited nervous system that reacts to selected external stimuli. 
         [0006]    Jellyfish depend entirely on factors other than themselves for horizontal movement; e.g., in nature winds, tides, and currents. Most jellyfish are, however, capable of some form of vertical motion and can orient themselves based upon their perception of light. 
         [0007]    In an aquarium environment jellyfish cannot generally be maintained in a rectangular tank because they are likely to become stuck in, or injure themselves at, corners or similar spaces. Accordingly, a jellyfish aquarium (sometimes referred to as a kreisel tank) whether large or small typically has curved or circular geometry, and is designed to replicate (or at least appropriately mimic) ocean currents or similar movement that keep jellyfish suspended in water while maintaining their equilibrium and natural shape. 
         [0008]    In such an aquarium, the water must move sufficiently to keep the jellyfish suspended and gently moving, but less than would injure the jellyfish or force them against the walls too aggressively. Furthermore, any pumps or other mechanical means for moving the water must avoid injuring or capturing the jellyfish. Because of their extremely low mass and fragile structure, jellyfish are easily drawn towards such outlets where they can become injured or die. Additionally, many jellyfish cannot tolerate air bubbles and thus any water-air mixtures or mixing devices (e.g., airstones) should be segregated from the jellyfish. 
         [0009]    From a filtration standpoint, a jellyfish aquarium must provide both the desired saltwater environment and means for removing waste materials produced by the jellyfish or that are byproducts of the other aquarium functions. In most aquariums, such materials will include ammonia and similar compounds produced from the ongoing biological processes. These compositions will at some point become disadvantageous or hazardous to the jellyfish. A typical jellyfish aquarium should also have a surface skimming capability and a filtration capability. Some (but not all) jellyfish need to be maintained at or near colder ocean temperatures. In such cases, water temperature should also be maintained at or near 55-65° F. in order to mimic the ocean environment. For such jellyfish, an aquarium typically includes a cooling system of some type (refrigeration unit; chiller). 
         [0010]    Because jellyfish are so fragile, such cooling and filtration systems are typically maintained separately from the aquarium tank itself and some piping and appropriate systems must be included to remove water from the aquarium, clean and chill the water, and return it to the aquarium tank; e.g., U.S. Pat. No. 7,610,878. 
       SUMMARY OF THE INVENTION 
       [0011]    An aquarium suitable for displaying jellyfish includes a chamber having interior walls that divide the chamber into a series of compartments. The first compartment is the viewing area having openings in the side walls that permit water to flow out of the viewing area while retaining jellyfish and flow into viewing area in a manner that keeps jellyfish suspended. A spillover riser is located between the first and second compartment that defines a channel through which the first and second compartment communicate. The second compartment has an air inlet providing the motive force to circulate water throughout the aquarium and introduce air bubbles to operate a foam fractionating device the inside the aquarium. The third compartment provides an area for placement of filter media and other necessary devices to keep jellyfish alive. The channel below the viewing area provides communication between the second and third compartment. 
         [0012]    The foregoing and other objects and advantages of the invention and the manner in which the same are accomplished will become clearer based on the followed detailed description taken in conjunction with the accompanying drawings. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a front elevational view of an aquarium according to the present invention. 
           [0014]      FIG. 2  is a perspective view of the aquarium of  FIG. 1 . 
           [0015]      FIG. 3  is a cross sectional view taken along lines  3 - 3  of  FIG. 2 . 
           [0016]      FIG. 4  is a side elevational view of the aquarium of  FIG. 1 . 
           [0017]      FIG. 5  is an opposite side elevational view from  FIG. 4 . 
           [0018]      FIG. 6  is a bottom plan view of the aquarium of  FIG. 1 . 
           [0019]      FIG. 7  is a cross-sectional view of a second embodiment of an aquarium according to the invention. 
           [0020]      FIG. 8  is a perspective view of a portion of the embodiment of  FIG. 7 . 
           [0021]      FIG. 9  is another partial perspective view of the second embodiment. 
           [0022]      FIG. 10  is another partial perspective view of the second embodiment. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0023]      FIGS. 1-6  illustrate a first embodiment of the aquarium. In this aspect, the aquarium includes a plurality of exterior walls that define a tank  20 . In operation, the tank  20  holds the water (usually salt water) that supports the jellyfish. The illustrated embodiment includes six exterior walls: a horizontally oriented top exterior wall  21 , respective vertically oriented side exterior walls  22  and  23 , a horizontally oriented bottom exterior wall  24 , and transparent front and rear walls  25  and  26 . Thus, in exemplary embodiments the overall shape of the tank  20  is a solid rectangle with front and rear walls having larger dimensions than the top, bottom and side walls  21 ,  22 ,  23 ,  24 . In other embodiments, the top exterior wall  21  can be eliminated and replaced (if desired) with a smaller cross brace between the front and rear walls  25 ,  26 . 
         [0024]      FIG. 1  illustrates the aquarium in a normal use orientation. At least the front and rear walls  25 ,  26  are formed of a polymer with at least the front wall being substantially transparent. In exemplary embodiments most or all of the parts illustrated and described herein are likewise formed of a polymer, and in some embodiments all of the structural parts are transparent. In general, any polymer that provides the structural strength necessary to hold the required amount of water, that is chemically inert with respect to both the seawater and the jellyfish (or other marine life), and that has the desired optical clarity will be suitable. Appropriate structural transparent polymers include, but are not limited to, acrylics, polycarbonates, and polyesters. 
         [0025]    In the illustrated embodiment, several rods  28  provide additional support between the front and rear walls  25 ,  26 . The illustrated embodiment includes four of the rods  28 . 
         [0026]    A cylindrical wall broadly designated at  27  is positioned within the tank  20  and spans the space between the front and rear walls  25 ,  26 . In that manner, the cylindrical wall  27  defines a cylindrical viewing area  30 . In an alternative embodiment, only the circular portion of the front wall  25  that is defined by the cylindrical wall  27  needs to be transparent in order to see the marine life (jellyfish) within the viewing area  30 . In some embodiments both the front and rear walls  25 ,  26  are transparent for viewing from either side. In other embodiments, the rear wall  26  is covered with a mirrored surface (typically a thin polymer film) that enhances the perceived depth of the viewing area  30 . If the rear wall  26  is transparent, the mirrored surface can be positioned on the outside of the rear wall  26 , and facing inwardly. Such an arrangement provides the desired mirrored surface without placing the mirror material inside the tank or in contact with salt (or fresh) water. If desired, the rear wall  26  can, of course, be opaque. 
         [0027]    A first upright interior wall  31  is located adjacent the cylindrical wall and defines a water inlet chamber broadly designated at  32 . In the illustrated embodiment, the wall  31  and a media screen  37  form an L-shape adjacent a vertically oriented spillover riser  33  in the water inlet chamber  32 . Water reaches the water inlet chamber  32  from the lower channel  38 . If a chiller is used, water circulates from the aquarium  20  to the chiller through the water outlet  60  and then returns through the water inlet  34 , both of which are positioned in the bottom exterior wall  24  and in communication with the water inlet chamber  32 . The water inlet and outlets  34 ,  60  can also be used to circulate water outside of the aquarium for any other desired or necessary reason. 
         [0028]    In the illustrated embodiment, the water inlet chamber  32  includes a plurality of media screens. A first media screen  35  is positioned at the bottom of the water inlet chamber  32 , a second media screen  36  is positioned in upper portions of the water inlet chamber  32  and a third media screen  37  is positioned midway along the water inlet chamber  32  adjacent the cylindrical wall  27  and the upright wall  31 . In exemplary embodiments, the screens are used to help position and maintain filtration media in various positions. In particular, a biological media can be positioned in the portions of the water inlet chamber designated at  40  and  41 . A chemical media is positioned in the portion of the water inlet chamber  32  that is labeled as  42 . 
         [0029]    As with the other interior components, the screens can be formed of an appropriate polymer. If formed of another material (e.g., a metal) the screens used to be inert with respect to the other items (salt water, marine life, etc.) in the same manner as the other components. Depending upon the nature of the filter media, one or more of the screens may be unnecessary. For example, fibrous materials will tend to stay in place without a screen more easily than will particles. 
         [0000]    Most of the waste generated by the jellyfish will be in the form of ammonia which is produced by the breakdown of proteins and which is toxic to most animals. Ammonia. Thus, as used herein, the term “biological medium” (or “biomedia”) refers to any appropriate media upon which organisms will grow that help convert the ammonia into nitrites, nitrates, and then nitrogen gas. The overall process is generally referred to as “nitrification.” 
         [0030]    The relevant nitrification organisms will tend to cultivate on gravel, or rocks, or other inert surfaces in the aquarium. In the present invention, any media that promote the growth of the desired organisms while otherwise remaining inert to the aquarium water and harmless to the jellyfish are appropriate. Appropriate media can include (but are not limited to) rocks and gravel, small plastic or ceramic objects, or small pieces of minerals such as quartz. 
         [0031]    As used herein “the term “chemical medium” tends to refer to filter media that do not necessarily encourage the growth of bacteria, but which have characteristics that otherwise help purify water that comes in contact with these materials. The most widely used chemical medium is activated carbon which, as known to the skilled person, helps purify the water by at least three processes: adsorption of particles onto the surface of the carbon based on static forces; diffusion of gases (which can help convert toxic ozone into oxygen) and chemosorption in which impurities chemically bind to the carbon. Generally, a given amount of activated carbon has finite adsorption capabilities and thus should be replenished on a periodic basis. 
         [0032]    Alternative chemical media can include ion exchange resins which purify the water by adding or removing specific ions. Such media are also referred to as deionizing resins. 
         [0033]    It will be nevertheless understood that in many cases, and even under the best conditions of physical, chemical, and biological filtration, fresh water (including sea water) will still be required on a time to time basis. The advantage of the invention, however, is in minimizing the need for such exchanges or other treatment. 
         [0034]    Because water moves cyclically through all of the portions of the aquarium, the “starting point” is arbitrary. Thus in one sense (and for descriptive purposes rather than limitation), water enters the tank  20  at the water inlet  34  and flows through a lower channel  38  that is defined between the bottom exterior wall  24  and a horizontal interior wall  39 . The water flows toward the media screen  35  and then into the water inlet chamber  32 . The water then travels upwardly over the biological media  40  to the chemical media  42  and then downwardly through the second portion of biological media  41 . The water then reaches the deflectors  43  in the cylindrical wall  27 . The deflectors  43  are movably attached to the respective openings  44  that permit incoming water to reach the viewing area  30 . The deflectors  43  help encourage water flowing through the openings  44  to move in a gentle laminar manner that enhances the growth and survival of the jellyfish. 
         [0035]    In different embodiments, the cylindrical wall  27  can be either unitary or formed of several separate wall portions. The illustrated embodiment includes four portions respectively designated at  45 ,  46 ,  47  and  50 . When constructed in this manner, the wall portions are both movable (to provide an opening into which marine life can be placed into the viewing area  30 ) and removable (typically for cleaning or replacement purposes). In that regard, the wall portions  45 ,  46 ,  47 ,  50  are positioned between respective circular grooves in the front and back walls  25 ,  26 . These grooves are congruent with the cylindrical wall  27  and thus not separately illustrated in  FIG. 1 . Additional grooves, however, are positioned in the front and back walls  25 ,  26  to permit movement. An arc groove  51  is illustrated just above the wall portion  50  in upper left-hand portions of the viewing area  30 . Linear grooves (i.e., one in front wall  25  and a parallel one in rear wall  26 )  52  extend from a position adjacent the wall portion  46  to the top exterior wall  21 . 
         [0036]    In one embodiment of the present invention, a semi-cylindrical wall  27  may be comprised of separate, removable sections which are also interchangeable to alter the water flow characteristics/pattern within the viewing area  30  of the tank. In another embodiment, the cylindrical wall  27  can be either unitary or formed of several separate wall portions. The cylindrical wall  27  may include four separate portions respectively designated at  45 ,  46 ,  47  and  50  as described previously. 
         [0037]    In the illustrated embodiment, a baffle  48  (optionally removable) is positioned adjacent the horizontal interior wall  39  and extends into the lower channel  38 . When water enters through the water inlet  34 , the baffle  48  helps prevent backflow towards the water outlet  60 . 
         [0038]    In use, in order to open or close the viewing area for access, the wall portion  46  can be moved in a counter clockwise direction into the arc groove  51 . Additionally, when the wall portion  46  is in the groove  51 , wall portion  47  can be raised and removed by sliding it counterclockwise to the linear grooves  52  and then out of the tank  20 . Wall portions  45  and  50  can be removed in the same manner. It will be understood that once one or two of the wall portions are removed, the others can be moved either clockwise or counterclockwise until they reach, and can be removed through, the linear grooves  52 . 
         [0039]    In the drawings, the arc groove  51  and the wall portion  50  are shown as slightly separated. This is for illustration purposes. In actuality, the wall portion  50  is positioned directly over the arc groove  51 . 
         [0040]    The removal step is enhanced by some of the additional illustrated features. In particular, the first interior wall  31  has a downwardly depending leg portion  53 . This downwardly depending portion  53  encourages the deflectors  43  to fold inwardly (i.e. towards the wall portion  47 ) as they pass and reach the depending portion  53  in order to facilitate their removal. 
         [0041]      FIG. 1  also illustrates that in this embodiment the aquarium tank  20  includes a second upright interior wall  54  which is adjacent to the cylindrical wall  27  and opposite (and as illustrated parallel to) the first upright wall  31 . The second upright wall  54  defines an air inlet chamber  55  between the cylindrical wall  27  and a different exterior wall, in particular the left side exterior wall  22  in the illustrated embodiment. A second spillover riser  57  is vertically oriented in the air inlet chamber  55 . 
         [0042]    An airstone holder  56  is positioned in lower portions of the air inlet chamber  55 . The airstone holder provides a position for an airstone (or “bubbler,” not shown) which can be supplied with air in any appropriate manner, with a flexible plastic tube (not shown) is typical. Aquarium airstones and their related parts (air pumps, tubes, etc.) are well understood in the art and will not be otherwise described in detail herein. As the figures illustrate, a small space between the return riser  64  and the airstone holder  56  permits water to flow into the air inlet chamber  55 . 
         [0043]    In operation, air (typically typically from a compressor or small pump, not shown) is sent to the air inlet chamber  55  from an airstone in the holder  56 . As air rises in the air inlet chamber  55 , it encourages water to flow in the same direction. When the water and air reach the top of the spillover riser  57 , air can escape through the froth chamber broadly designated at  61 . Meanwhile, the water reverses direction and travels downwardly along the side exterior wall  22  and from there to the water outlet  60  in the bottom exterior wall  24  of the tank  20 . As the water travels downwardly, any remaining air bubbles tend to separate and rise upwardly. As a result, the possibility of air bubbles reaching the viewing area is minimized or eliminated. 
         [0044]    The overall water flow in the illustrated embodiment thus proceeds as follows. Water enters through the inlet  34  in the bottom exterior wall  24  and then moves into the water inlet chamber  32  which contains the biological media  40 . The water travels upwardly through the biological media  40  through the media screen  36  and then through the chemical media  42  in the top portion of the water inlet chamber  32 . The water then travels downwardly through the second set of biological media  41  in the water inlet chamber  32  through the media screen  37  and then to those portions of the tank  20  that are adjacent the deflectors  43  and the openings  44 . The water then flows into the viewing area  30  over the deflectors  43  and through the openings  44 . The water exits the viewing area through the perforations or slots  63  in the upper right-hand wall portion  46 . The water then moves along the top of the tank  20  but outside of the viewing area  30  towards a return riser (or overflow bulkhead)  64  which includes a comb  65  in its upper portions which helps enhance surface skimming of debris and some organic compositions from the moving water. The water then moves downwardly through the narrow space defined between the return riser  64  and the second upright interior wall  54  until the water reaches the bottom left-hand portion of the tank  20  adjacent the airstone holder  56 . In some embodiments, the return riser  64  and the wall portion  45  can be formed of a single piece. Because of their respective positions, neither needs to be removed to provide access to the viewing area  30 . 
         [0045]    As set forth previously, air is pumped into the tank and provides the mechanical force to move the water in the indicated manner. The water moves upwardly through the air inlet chamber  55  to the top of the spillover riser  57 . At this point, because the water has exited the viewing area, it is likely to carry various contaminants with it. Some of the contaminants will typically mix with the water and air (i.e., cling to the surface of air bubbles) to create a froth that rises into the froth chamber  61 . 
         [0046]    The froth chamber  61  is formed of a collection cup  66  (exterior) and an interior froth tube  67 . When froth moves upwardly from the air inlet chamber  55  through the froth tube  67  it reaches a downwardly depending deflector  70  at the top of the froth chamber which encourages it to move into the collection cup  66  from which it can be manually removed. In the illustrated embodiment, the deflector  70  is in the form of a short, and thus relatively broad, tube. 
         [0047]      FIG. 7  is a cross-sectional view of a second embodiment of the invention. A number of the elements are either identical or nearly-identical to those of the first embodiment and accordingly carry common reference numerals. These include the tank broadly designated at  20 , the cylindrical viewing area  30 , the sidewalls  22  and  23 , and the bottom wall  24 . Other common elements include the cylindrical wall  27  that defines the viewing area  30 , the biomedia area  40 , the chemical media area  42 , the air inlet holder  56 , and the return riser  64 . The froth chamber broadly designated at  61  is also essentially the same as the one already described. 
         [0048]    Some of the different aspects will be clearly understood with respect to  FIGS. 7-10 , and particularly when described in the context of the direction of water flow in  FIG. 7 . First, when an air stone is placed in the holder  56 , bubbles pumped though such an airstone rise through a tube  72  in the air inlet chamber broadly designated at  55 . The top of the tube  72  now represents the outlet position for water leaving the air inlet chamber  55 . 
         [0049]    As in the previous embodiment, bubbles rising from an air stone encourage water to flow with the bubbles, and out of the air inlet chamber  55  to the space between the tube  72  and the interior wall  54 , and then downwardly to the lower portions of the tank  20  outside of the viewing area  30 . The tube  72  above the airstone in the holder  56  can help pull water somewhat more effectively than some other structures. Additionally, positioning the air inlet further above the bottom wall  24  and more towards the mid level of the tank  20  creates extra space in the lower corner which in turn helps encourage a more effective air separation. 
         [0050]    As in the previous embodiment, the air inlet chamber  55  is defined by the sidewall  22  and a vertical interior wall  54 . Water flows downwardly between the tube  72  and the wall  54  toward the diagonally disposed plate  73  and then past the outside of the cylindrical wall and then adjacent the bottom wall  24 . The water then flows through a media screen (not shown) at or near the bottom of the biomedia space  40  into the biological medium in the space  40 , and then into the chemical media  42 . The chemical a biomedia spaces  40 , 42  are separated by the media screen  36 . The water then moves from the chemical media area  42  through another media screen  74  into an upper portion of the tank  20  (i.e., illustrated as the upper right portion of  FIG. 7 ). 
         [0051]    In comparison to the water flow path of the first embodiment, the water enters the viewing area  30  through a plurality of openings (not visible in the perspective views) in an upper portion of the cylindrical wall  27  that faces the general corner defined by the vertical media screen  74  and the top of the tank  20 . 
         [0052]    From the viewing area  30 , water flows through openings (e.g.,  81  in  FIG. 10 ) to the return riser  64 . The water passes through openings  80  (e.g.,  FIG. 8 ) in the return riser  64  and then downwardly to the opening  58  in the air inlet chamber  55  adjacent the air stone holder  56 . 
         [0053]    A pair of braces  76  helps support the front and rear walls  25  and  26  (which are not visible in the cross-section of  FIG. 1 ).  FIG. 7  also shows a sliding door  77  that moves vertically to adjust the flow of water through the return riser  64 , and thus helps control the overall flow rate in the tank  20 , including the particular velocity of water movement in the viewing area  30 . 
         [0054]      FIG. 8  is a perspective view of an upper corner of the second embodiment.  FIG. 8  illustrates the front wall  25  (which is always transparent) and the rear wall  26  which can be transparent, mirrored, or opaque.  FIG. 8  illustrates that the return riser  64  includes a plurality of slotted openings  80 . Water that has left the circular viewing area  20  returns over the riser  64  through these slots  80 . The sliding door  77  can be vertically adjusted to raise or lower the position at which water flows through the slots. 
         [0055]      FIG. 8  also illustrates that water leaves the cylindrical viewing area  30  through the slots  81  in a portion of the cylindrical wall  27 . The slots  81  need to be sized for appropriate water flow, but without creating suction or vortex flow that is strong enough to draw the jellyfish into the openings and hold there.  FIG. 8  also illustrates a set of grooves (one is illustrated)  52  through which segments of the cylindrical wall can be removed in a manner previously described with respect to the first embodiment. The portion of the cylindrical wall  27  that holds the slots  81  typically extends to the top of the tank  20  (e.g.,  FIG. 10 ), but for clarity,  FIG. 8  illustrates only a portion of this. The slots  81  may be located on any portion of the cylindrical wall  27 . 
         [0056]      FIG. 9  is another partial perspective view of the (as illustrated) right-hand portion of the tank  20 . In particular,  FIG. 9  illustrates a filling of support material  82  of the type previously described that will encourage the growth of a biological media which in turn filters water passing through it. A corresponding chemical media can be positioned in the space  42  that is separated from  40  by a media screen  36 . As  FIG. 9  further illustrates, another media screen  74  with a plurality of slots holds the chemical media in place as water flows in the direction indicated by the arrows. 
         [0057]      FIG. 9  also shows a small opening  83  that allows any accumulated microbubbles—that might otherwise form in the (as illustrated) lower right-hand corner of the tank  20 —to move into the biofiltration area  40 . In particular, the cylindrical wall  27 , the bottom wall  24 , and the interior wall  31  for the biomedia area  40  define a quasi-triangular shaped area into which microbubbles can gather into one or more larger bubbles which then move into the biological medium  82  from where they will tend to rise to the top of the tank  20  without negatively affecting the jellyfish in the viewing area  30 .  FIG. 9  also helps illustrate that in this embodiment water returns to the circular viewing area  30  through an upper portion of the circular wall  27  rather than a lower portion as in the first embodiment. The small opening  83  may also be located on any surface within the tank where bubbles or microbubbles may accumulate in order to aid in their dispersion. 
         [0058]      FIG. 10  shows some of the similar details as  FIGS. 7 and 8  but in particular illustrates that the slots  81  through which water travels from the cylindrical viewing area  30  towards the return riser  64  extend along a significant portion of the cylindrical wall  27 , and then extend further along a common piece all the way to the top of the aquarium tank  22 ; i.e., a position adjacent the top of the front and rear walls  25 ,  26 .  FIG. 10  also illustrates the presence of an optional brace  68  between the front and rear vertical walls,  25 ,  26 . One or more of such braces can be added between the walls as may be desired or necessary. 
         [0059]    In one embodiment of the present invention, the air inlet chamber  55 , in conjunction with the collection cup  66  within the froth chamber  61 , forms a foam fractioning device/protein skimmer. Foam fractionation is a chemical process in which hydrophobic molecules are preferentially separated from a liquid solution using rising columns of foam. It is commonly used, albeit on a small scale, for the removal of organic waste from aquariums; these units are known as “protein skimmers”. However it has much broader application in the chemical process industry and can be used for the removal of surface active contaminants from waste water streams in addition to the enrichment of bio-products. Foam fractionation is closely related to the process of froth flotation in which hydrophobic particles attach to the surface of bubbles which rise to form a pneumatic (i.e. rising) foam. In this way, relatively hydrophobic particles can be separated from relatively hydrophilic particles. In one embodiment, the protein skimmer could have more than one air inlet chamber  55  (acting as an airlift tube to circulate the water in the tank). In another embodiment, there could be more than one air stone. In yet another embodiment, there could be more than one outlet and/or more than one inlet within the air inlet chamber  55 . In still another embodiment, the orientation and locations of the air stone(s), outlet(s) and/or inlet(s) may be altered and rearranged. In yet another embodiment, a foam fractioning device/protein skimmer is a separate, stand-alone device which may be inserted and/or withdrawn from a suitable location within a tank which permits its proper functioning. 
         [0060]    In one embodiment of the present invention, the material depicted in  FIG. 9  as biological media  40  located within the water inlet chamber  32  may function as a filter through which the water in the tank passes as it cycles through the tank. The water inlet chamber  32  includes a plurality of media screens. A first media screen  35  is positioned at the bottom of the water inlet chamber  32 , a second media screen  36  is positioned in upper portions of the water inlet chamber  32  and a third media screen  37  is positioned at the top of the water inlet chamber  32  adjacent the cylindrical wall  27  and the upright wall  31 . In exemplary embodiments, the screens are used to help position and maintain filtration media in various positions. In particular, a biological media can be positioned in the portions of the water inlet chamber designated at  40  and  41 . A chemical media is positioned in the portion of the water inlet chamber  32  that is labeled as  42 . 
         [0061]    In one embodiment of the present invention, an air inlet foam fractioning device/protein skimmer is in direct communication with a water inlet chamber  32  which may include filtration media. In another embodiment, an aquarium as described in any of the previous embodiments, further includes a water outlet in communication with a filtration compartment  40  at the opposite end of a riser from the filtration compartment&#39;s water inlet. 
         [0062]    In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms have been employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims