Patent Publication Number: US-2006000755-A1

Title: Aquarium arrangement

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is a continuation-in-part of application Ser. No. 10/868,749, filed Jun. 15, 2004; which application is incorporated herein by reference. 
    
    
     TECHNICAL FIELD  
      This disclosure relates generally to decorative structures for use with aquariums. In particular, this disclose relates to a decorative structure configured to conceal a filter assembly and heater.  
     BACKGROUND  
      A wide variety of aquarium decor is available for use in enhancing the beauty and enjoyment of an aquarium. In some applications, the aquarium decor is used to conceal aquarium accessories such as circulating conduits, aeration conduits, filter assemblies, heaters, or other accessories. These accessories are generally associated with maintaining a healthy environment for aquatic life within the aquarium. For example, these types of accessories are important to maintaining proper temperature regulation, water circulation, and water filtration. While aquarium decor adds aesthetic value to an aquarium, use of decor to conceal aquarium components can hinder the effectiveness of the components needed to maintain a healthy aquatic environment.  
      In general, improvement has been sought with respect to such arrangements and methods, generally to improve the aesthetic quality of an aquarium while still maintaining, and even enhancing the effectiveness of components associated with the environmental quality of the aquarium.  
     SUMMARY  
      The present invention concerns a decorative aquarium arrangement having a decorative structure for use in concealing a filter assembly and a heater. The decorative structure has a front side and a back side, the back side defining a cavity within which the filter assembly and the heater are positioned. The decorative structure also includes an inlet and an outlet. One feature of the arrangement relates to the offset position of the inlet and the outlet, which creates a diagonal circulation of aquarium water within an aquarium. Another feature of the arrangement relates to the proximate position of the heater in relation to the filter assembly, which thereby dispenses heated filtered water via a spillway to the primary volume of water of the aquarium.  
      A variety of examples of desirable product features or methods are set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practicing various aspects of the disclosure. The aspects of the disclosure may relate to individual features as well as combinations of features. It is to be understood that both the foregoing general description and the following detailed description are explanatory only, and are not restrictive of the claimed invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a front perspective view of one embodiment of an aquarium decor arrangement, according to the principles of the present disclosure, shown positioned in an aquarium;  
       FIG. 2  is a front perspective view of the aquarium arrangement of  FIG. 1 ;  
       FIG. 3  is a rear perspective view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 4  is a front elevation view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 5  is a top plan view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 6  is a side elevation view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 7  is a back elevation view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 8  is a bottom plan view of the aquarium arrangement of  FIG. 2 ;  
       FIG. 9  is a front perspective view of another embodiment of an aquarium decor arrangement, according to the principles of the present disclosure;  
       FIG. 10  is a rear perspective view of the aquarium arrangement of  FIG. 9 ;  
       FIG. 11  is a front elevation view of the aquarium arrangement of  FIG. 9 ;  
       FIG. 12  is a back elevation view of the aquarium arrangement of  FIG. 9 ;  
       FIG. 13  is a bottom plan view of the aquarium arrangement of  FIG. 9 ;  
       FIG. 14  is a front perspective view of yet another embodiment of an aquarium decor arrangement, according to the principles of the present disclosure;  
       FIG. 15  is a rear perspective view of the aquarium arrangement of  FIG. 14 ;  
       FIG. 16  is a front elevation view of the aquarium arrangement of  FIG. 14 ;  
       FIG. 17  is a top plan view of the aquarium arrangement of  FIG. 14 ;  
       FIG. 18  is a back elevation view of the aquarium arrangement of  FIG. 14 ;  
       FIG. 19  is a bottom plan view of the aquarium arrangement of  FIG. 14 ;  
       FIG. 20  is a front perspective view of still another embodiment of an aquarium decor arrangement, according to the principles of the present disclosure;  
       FIG. 21  is a rear perspective view of the aquarium arrangement of  FIG. 20  and shows a back panel of the arrangement;  
       FIG. 22  is a back elevation view of the aquarium arrangement of  FIG. 21 , shown with the back panel removed;  
       FIG. 23  is a front elevation view of the aquarium arrangement of  FIG. 20 ; and  
       FIG. 24  is a side elevation view of the aquarium arrangement of  FIG. 20 . 
    
    
     DETAILED DESCRIPTION  
      Reference will now be made in detail to various features of the present disclosure that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.  
       FIGS. 1-8  illustrate one embodiment of an aquarium decor arrangement  10  in accord with the principles of the present disclosure. The aquarium arrangement  10  is typically placed within an aquarium or tank  20 . In the illustrated embodiment, the aquarium arrangement  10  includes a decorative structure  12 , a filter assembly  14 , and a heater  16 .  
      The aquarium arrangement  10  is constructed and arranged such that a diagonal circulation of water flow (shown in  FIG. 1 ) is created within the aquarium  20  when aquarium water is circulated through the arrangement  10 . Water circulation generated by conventional arrangements typically involves an up and down flow circulation in contrast to a circulation having a side-to-side flow component. The present arrangement  10  is designed to generate a side-to-side flow component sufficient to create the diagonal circulation of water within an aquarium and thereby reduce stagnant water regions within the aquarium. In conventional arrangements, stagnant water regions are a common problem because the up and down circulation tends to produce such circulation in only portions or isolated regions of the aquarium. As will be discussed in greater detail hereinafter, the diagonal circulation provided by the present arrangement has an effect on a larger majority of a volume of water contained with an aquarium. Thereby, the diagonal circulation of the present arrangement  10  reduces the occurrence of stagnant water regions.  
      Referring now to  FIGS. 2 and 3 , the decorative structure  12  of the arrangement  10  has a front side or surface  22  and a back side or surface  24 . The front side  22  typically includes features or structures  18  designed to make the aquarium&#39;s appearance more natural, beautiful, and enjoyable. In the illustrated embodiment of  FIGS. 1-8 , the features of the decorative structure  12  are designed in the form of underwater roots. In other embodiments shown in  FIGS. 9-13  and  FIGS. 20-24 , the features are designed in the form of an underwater stump; and in  FIGS. 14-19 , the features are designed in the form of another underwater root system. Other designs that enhance the appearance of an aquarium are within the scope of the present disclosure. For example, the features  18  can be in the form or coral or other underwater structures.  
      Referring now to  FIGS. 1 and 4 , the decorative structure  12  has a first end  26  and a second end  28 . When positioned within an aquarium  20 , preferably the first end  26  of the structure  12  rests upon a bottom  30  ( FIG. 1 ) of the aquarium  20 . Positioning the structure  12  to rest upon the bottom  30  of the aquarium  20  includes placing the first end  26  of the structure  12  on a bottom surface of the aquarium, on a gravel layer at the bottom of the aquarium, on a liner positioned at the bottom of the aquarium, or on other structure located at the lower or bottom region of the aquarium.  
      The second end  28  of the structure  12  is preferably located above the waterline of the aquarium  20  ( FIG. 1 ) when the first end  26  of the structure  12  rests upon the bottom  30 . In general, the structure  12  has a height H that extends from the first end  26  to the second end  28 ; the height H is sized so that the second end  28  of the structure  12  extends out of the water to provide easy access to the filter assembly  14  and the heater  16  when the arrangement  10  is positioned within the aquarium  20 . In some embodiments, the height H corresponds to a full height of the aquarium  20 .  
      Referring now to  FIGS. 3 and 5 , the back side  24  of the decorative structure  12  defines a volume or cavity  32  that is separate from a primary volume  34  ( FIG. 1 ) of the aquarium  20 . A top opening  36  at the second end  28  of the structure  12  provides access to the cavity  32  defined by the back side  24  when the structure  12  is positioned adjacent a back wall  21  of an aquarium  20 . In the illustrated embodiment, the cavity  32  is formed by a curved contour of the back side  24  and first and second side walls  46 ,  47  of the decorative structure  12 . The cavity  32  is configured to conceal the filter assembly  14  and the heater  16  when positioned within the cavity. Preferably, both the filter assembly  14  and the heater  16  are internal to the aquarium  20 , rather than, for example, an arrangement having a filter assembly that is mounted outside of the aquarium.  
      Referring now to  FIGS. 5 and 6 , the decorative structure  12  defines a water circulation inlet  38  and a water circulation outlet  40 . The inlet  38  provides fluid communication from the primary volume  34  of the aquarium  20  to the cavity  32  located behind the structure  12 . The outlet  40  provides fluid communication from the cavity  32  of the structure  12  to the primary volume  34  of the aquarium  20 .  
      Referring back to  FIG. 2 , the outlet  40  of the structure  12  is generally a location  72  at which water exits the decorative structure  12 . In other words, the outlet  40  typically is defined by the location  72  at which the filter assembly  14  is positioned, and does not require a particular structurally-defined outlet. The filter assembly  14  generally includes a submersible pump  78  ( FIG. 7 ) defining a filter assembly inlet  58 , and a filter housing  54  defining a filter assembly outlet  60  ( FIG. 2 ). The filter assembly outlet  60  in the illustrated embodiment is a spillway  68 . A spillway is generally an edge, ledge or surface over which water flows, in contrast to a port, for example. The location  72  at which the spillway  68  is positioned at least partially defines the outlet  40  of the decorative structure  12  in the embodiment of  FIGS. 1-8 .  
      Although no particular structurally-defined outlet is required by the present disclosure, in the illustrated embodiment, the outlet  40  is also partially defined by a recessed lip  50  ( FIGS. 2 and 3 ) formed along a top edge  52  of the decorative structure  12 . The lip  50  is sized to accommodate the spillway  68  of the filter assembly  14 . Other embodiments may or may not include specific structure corresponding to the configuration of the filter assembly  14 . It is further contemplated that the water circulation outlet  40  may include, for example, channels, openings, or other outlet structures that direct water back into the primary volume  34  of the aquarium. During operation, water is returned to the primary volume  34  of the aquarium  20  at the location  72  of the lip  50 . In particular, water exits the spillway  68  formed in the filter housing  54  of the filter assembly  14 , which is positioned at the lip  50  of the decorative structure  12 .  
      Preferably, the location  72  at which water is dispensed from the arrangement  10  to the primary volume  34  of the aquarium  20  is located at a surface level of the water within the aquarium. Water exiting the structure  12  at the surface level of the aquarium water creates a ripple effect on the surface of the water. The ripple effect increases the oxygen level of the aquarium water to aid in maintaining a healthy aquatic environment. Alternatively, the location  72  at which water is dispensed from the arrangement may be located above the surface level of the water within the aquarium to create a waterfall effect. Similarly, it is contemplated that water may be dispensed from the arrangement  10  at a location below the surface level of the aquarium water.  
      Referring back to  FIGS. 3 and 6 , the inlet  38  of the structure  12  includes at least one opening, preferably a plurality of openings  44 , formed in one of the side walls  46 ,  47  of the decorative structure  12 . In the illustrated embodiment, the plurality of openings  44  is defined by a grill piece  42  inserted within a notch  66  formed in the first side wall  46 . In an alternative embodiment, the plurality of openings  44  may be formed directly within one of the side walls  46 ,  47  of the structure  12 . The number and size of the openings  44  are configured to accommodate a particular flow rate produced by the filter assembly  14 .  
      Referring back to  FIG. 7 , the outlet  40  of the structure  12  is located at the second end  28  of the decorative structure  12 , while the inlet  38  is located adjacent the first end  26  of the structure. In addition, the outlet  40  is located adjacent to one of the side walls (e.g. the second side wall  47 ) of the structure  12 , while the inlet  38  is located at the opposite side wall (e.g. the first side wall  46 ) of the structure. The relative locations of the structure inlet  38  and the structure outlet  40  create the diagonal circulation of water flow within the aquarium  20 , which reduces the occurrence of stagnant water regions.  
      In particular, the relative locations of the inlet  38  and the outlet  40  are such that each of the inlet  38  and outlet  40  are positioned a vertical distance D 1  and a horizontal distance D 2  from one another. Preferably, the horizontal distance D 2  is at least half as great as the vertical distance D 1  (each of the distances being defined between centerlines of the inlet and outlet structures). The relative positioning of the structure inlet and outlet  38 ,  40  generates a side-to-side flow component that creates the diagonal circulation of aquarium water to reduce stagnant regions within the aquarium. In one embodiment, the horizontal distance D 2  is between about 5.0 and 6.0 inches and the vertical distance D 1  is between about 6.0 and 9.0 inches for an aquarium ranging between 10 and 30 gallons; although the disclosed principles can be applied in a variety of sizes and applications.  
      Likewise, the filter assembly  14  is typically positioned within the cavity  32  so that the filter assembly inlet  58  is positioned a distance D 3  from the structure inlet  38  to create a substantially horizontal flow of water (represented by arrows A in  FIG. 7 ) between the structure inlet  38  and the filter assembly inlet  58 . The substantially horizontal flow of water creates a flow vector that contributes to the side-to-side flow component ( FIG. 5 ) of the diagonal circulation ( FIG. 1 ) of aquarium water to reduce stagnant regions within both the cavity  32  and the primary volume  34  of the aquarium  20 . In one embodiment, the distance D 3  between the structure inlet  38  and the filter assembly inlet  58  is between about 2.0 and 3.5 inches; although the disclosed principles can be applied in a variety of sizes and applications.  
      The side-to-side flow component produced by the present arrangement  10  reduces stagnant water by creating a circulation within the aquarium that captures and draws a greater percentage of water within its flow than conventional arrangements. As previously described, conventional arrangements create an up and down circulation having a path length within a particular sized aquarium. The path length of the up and down circulation is less than a path length of a diagonal circulation created within that same aquarium. Accordingly, the diagonal circulation having the side-to-side flow component reduces stagnant water within the aquarium by capturing and drawing a greater percentage of water within its flow, as compared to conventional arrangements.  
      Further, to enhance the diagonal circulation created by the disclosed arrangement  10 , the decorative structure  12  preferably has a width W 1  ( FIG. 5 ) suited to the size and width W 2  of the aquarium  20 . As can be understood, the width W 1  structurally defines the boundaries of the horizontal distance D 2  between the water circulation inlet  38  and the water circulation outlet  40  of the decorative structure  12 . In the preferred embodiment, the width W 1  of the structure  12  is at least 25% of the width W 2  of the aquarium  20 .  
      Referring now to  FIGS. 6 and 7 , the openings  44  of the structure inlet  38  and the heater  16  are arranged such that water flowing through the inlet  38  is in thermal communication with the heater  16  positioned within the cavity  32  of the structure  12 . The openings  44  are located so that a significant majority of the water flow passes across a heating element  48  of the heater  16  prior to filtration. In the illustrated embodiment, the openings  44  are arranged in a generally vertical array to correspond to the elongated construction of the heater element  48 . In operation, water is drawn through the plurality of openings  44 , across the heating element  48 , and into the filter assembly inlet  58 .  
      In the illustrated embodiment, the heater  16  is positioned in close proximity to the filter assembly  14  so that water flowing into the filter assembly  14  is heated immediately prior to entering the filter assembly inlet  58 . What is meant by close proximity is that that heater  16  is located closer to the filter assembly inlet  58  than to the structure inlet  38 . When positioned in close proximity, the heated water enters the filter assembly inlet  58  for filtration; and both heated and filtered water is returned to the primary volume  34  of the aquarium  20 .  
      Heating the flow of water immediately prior to being drawn into the filter assembly for filtration effectively regulates the temperature of the aquarium water. That is, by returning heated, filtered water to the primary volume  34  of the aquarium  20 , and creating a diagonal circulation within the aquarium, the heated, filtered water is better dispersed within the aquarium to provide a more uniform temperature throughout the aquarium. In conventional arrangements, heaters are typically arranged such that water is heated by conduction. The conductively heated water is circulated only by means of the general circulation of the primary volume of the aquarium water. Because the heated water of conventional arrangements is not dispensed into the primary volume of the tank, and is not dispersed by drawing the heated water into a diagonal circulation that reduces stagnant regions, problems of poor temperature regulation and/or water pockets having varying temperatures often arise.  
      As can be seen in  FIG. 4 , the decorative structure  12  conceals the filter assembly  14  and heater  16  to enhance the appearance of the aquarium  20 . While hidden from view, the filter assembly  14  and heater  16  are still easily accessible because of the configuration of the structure&#39;s height H. For example, as shown in  FIG. 2 , the filter assembly  14  is accessible from the opening  36  at the second end  28  of the structure  12 . A person can remove, replace and/or maintenance the filter assembly  14  without immersing one&#39;s hands in the aquarium water. Similarly, the heater  16  is accessible from the opening  36  at the second end  28  of the structure  12 . A person can adjust the heater  16  without immersing one&#39;s hands in the water.  
      In the illustrated embodiment, the filter assembly  14  is typically mounted to the edge  64  of the aquarium  20  by a bracket (not shown). The structure  12  of the arrangement  10  is preferably sized such that the filter assembly outlet  60  is located at or adjacent to the water circulation outlet  40  when the filter assembly  14  is mounted to the edge  64  of the aquarium  20 . The heater  16  may be mounted to the filter assembly  14 , to the structure  12 , to the aquarium edge  64 , or, as shown in the illustrated embodiment in  FIGS. 2, 3  and  5 , mounted to a divider wall  74 .  
      The divider wall  74  in the illustrated embodiment includes an opening  76  ( FIG. 7 ) through which the heated water flows to enter the filter assembly inlet  58 . The divider wall  74  directs the flow of the water so that only water that has been in thermal communication with the heater  16  enters the filter assembly  14 . To aid in creating the horizontal flow of water shown in  FIG. 7 , the opening  76  of the divider wall is located across from (e.g. in approximate horizontal alignment with) the inlet  38  of the structure  12  and the filter assembly inlet  58  of the filter assembly  14 .  
      Referring now to  FIGS. 3 and 8 , the arrangement  10  can further include an aeration device  80 . In the illustrated arrangement  10 , the aeration device  80  includes an air stone  82  interconnected to an airline  84 . The airline  84  extends into the cavity  32  of the structure and through an opening  86  formed in a bottom  90  of the structure  12 . The airline is then routed through a channel or slot  88  that extend to the front side  22  of the structure  12 . The air stone  82  is porous to permit air from the airline  84  to bubble out of the air stone  82 . In the illustrated embodiment of  FIGS. 1-8 , the air stone  82  is positioned at the front side  22  of decorative structure  12 . During operation of the aeration device  80 , air bubbles up the front side  22  of the structure  12  to add further interest to the aesthetic appeal of aquarium arrangement  10  while oxygenating the aquarium water.  
      In use, the aquarium arrangement  10  creates a flow of fluid that effectively circulates water throughout the aquarium to reduce dead spots or stagnant water regions within both the cavity  32  of the structure  12  and the primary volume  34  of the aquarium  20 . In conventional arrangements, water can become trapped behind simple backdrop liners, or become stagnant in remote regions of the aquarium. In the disclosed arrangement  10 , the filter assembly  14  is positioned to draw water from the primary volume  34 , through the water circulation inlet  38  of the structure  12 , across the heating element  48  of the heater  16  and into the filter assembly  14 . The heated, filtered water is then directed out the water circulation outlet  40  of the structure and dispersed across the water surface of the aquarium  20 . The diagonal circulation created by the disclosed arrangement  10  not only reduces stagnant water regions with the aquarium, but even enhances the effectiveness of the filter assembly  14  and the heater  16 .  
      Referring now to  FIGS. 9-13 , a second embodiment of an aquarium decor arrangement  100  is illustrated. In this embodiment, the aquarium arrangement  100  also includes a decorative structure  112 , a filter assembly  114 , and a heater  116 .  
      Similar to the previous embodiment, the aquarium arrangement  100  is constructed and arranged such that a diagonal circulation of water flow is created within the aquarium  20  when aquarium water is circulated through the arrangement  100 . Likewise, many of the structural features of the aquarium arrangement  100  are similar to that of the previous embodiment.  
      For instance, referring to  FIGS. 9 and 10 , the decorative structure  112  has a front side  122  and a back side  124 , and a first end  126 , a second end  128 . When positioned within an aquarium  20 , the first end  126  of the structure  112  rests upon the bottom  30  ( FIG. 1 ) of the aquarium  20 . The back side  124  of the decorative structure  112  defines a volume or cavity  132  that is separate from the primary volume  34  ( FIG. 1 ) of the aquarium  20 . A top opening  136  at the second end  128  of the structure  112  provides access to the cavity  132  defined by the back side  124  of the structure  112  when the structure  112  is positioned adjacent a back wall  21  of an aquarium  20 . The cavity  132  is configured to conceal the filter assembly  114  and the heater  116  when positioned within the cavity.  
      Referring now to  FIGS. 10-12 , the decorative structure  112  defines a water circulation inlet  138  and a water circulation outlet  140 . The inlet  138  provides fluid communication from the primary volume  34  of the aquarium  20  to the cavity  132  located behind the structure  121 . The outlet  140  provides fluid communication from the cavity  132  of the structure  112  to the primary volume  34  of the aquarium  20 .  
      The inlet  138  of the structure  112  includes at least one opening, preferably a plurality of openings  144 , formed in one of a first side wall  146  and a second side wall  147  of the decorative structure  12 . In the second embodiment, the plurality of openings  144  are defined by a grill piece  142  inserted within a notch  166  ( FIG. 10 ) formed in the first side wall  146 .  
      Referring to  FIG. 11 , the outlet  140  of the structure  112  is located at the second end  128  of the decorative structure  112 , while the inlet  138  is located adjacent the first end  126  of the structure. In addition, the outlet  140  is located adjacent to one of the side walls (e.g. the second side wall  147 ) of the structure  112 , while the inlet  138  is located at the opposite side wall (e.g. the first side wall  146 ) of the structure.  
      The relative locations of the structure inlet  138  and the structure outlet  140  generate a side-to-side flow component that creates the diagonal circulation of aquarium water to reduce stagnant regions within the aquarium  20 . In addition, the filter assembly  114  is typically positioned within the cavity  132  so that a filter assembly inlet  158  ( FIG. 12 ) is positioned a distance from the structure inlet  138  to create a substantially horizontal flow of water between the structure inlet  138  and the filter assembly inlet  158 , as previously described.  
      Still referring to  FIG. 12 , the heater  116  is positioned in close proximity to the filter assembly  114  so that water flowing into the filter assembly  114  is heated immediately prior to entering the filter assembly inlet  158 . Heating the flow of water immediately prior to being drawn into the filter assembly  114  for filtration effectively regulates the temperature of the aquarium water.  
      Referring now to  FIG. 13 , the arrangement  100  further includes an aeration device  180 . In the illustrated arrangement  100 , the aeration device  180  includes an air stone  182  interconnected to an airline  184 . The airline  184  extends into the cavity  132  ( FIG. 12 ) of the structure  112  and through an opening  186  formed in a bottom  190  of the structure  112 . The airline is then routed through a channel or slot  188  that extend to a secondary chamber  192  formed in the bottom  190  of the structure  12 . A plurality of holes  194  is formed adjacent to one of the side walls (e.g. the first side wall  146 ). The air stone  82  is porous to permit air from the airline  84  to bubble out of the air stone  82  and through the holes  194 .  
      Referring now to  FIGS. 14-19 , a third embodiment of an aquarium decor arrangement  200  is illustrated. In this embodiment, the aquarium arrangement  200  also includes a decorative structure  212 , a filter assembly  214 , and a heater  216 .  
      Similar to the previous embodiments, the aquarium arrangement  200  is constructed and arranged such that a diagonal circulation of water flow is created within the aquarium  20  when aquarium water is circulated through the arrangement  200 . Likewise, some of the structure features of the aquarium arrangement  200  are similar to that of the previous embodiments.  
      For example, referring now to  FIGS. 14 and 15 , the decorative structure  212  of the arrangement  200  has a front side  222  and a back side  224 , and a first end  226  and a second end  228 . When positioned within an aquarium  20 , the first end  226  of the structure  212  rests upon a bottom  30  ( FIG. 1 ) of the aquarium  20 . The back side  224  of the decorative structure  212  defines a volume or cavity  232  that is separate from a primary volume  34  ( FIG. 1 ) of the aquarium  20 . A top opening  236  at the second end  228  of the structure  212  provides access to the cavity  232  defined by the back side  224  when the structure  212  is positioned adjacent a back wall  21  ( FIG. 1 ) of an aquarium  20 . The cavity  232  is configured to conceal the filter assembly  214  and the heater  216  when positioned within the cavity.  
      Still referring to  FIGS. 14 and 15 , the decorative structure  212  defines a water circulation inlet  238  and a water circulation outlet  240 . The inlet  238  provides fluid communication from the primary volume  34  of the aquarium  20  to the cavity  232  located behind the structure  212 . The outlet  240  provides fluid communication from the cavity  232  of the structure  212  to the primary volume  34  of the aquarium  20 . The outlet  240  of the structure  212  is generally a location  272  at which water exits the decorative structure  212 .  
      The filter assembly  214  includes a submersible pump  278  ( FIG. 15 ) defining a filter assembly inlet  258  ( FIG. 18 ) and a filter housing  254  defining a filter assembly outlet  260  ( FIG. 17 ). The filter assembly outlet  260  in the illustrated embodiment is a spillway  268 . The location  272  at which the spillway  268  is positioned defines the outlet  240  of the decorative structure  212 .  
      Referring now to  FIGS. 14 and 18 , the inlet  238  of the structure  212  includes at least one opening, preferably a plurality of openings  244 , formed along a bottom edge  227  of the decorative structure  212 . The outlet  240  of the structure  212  is located at the second end  228  of the decorative structure  212 , while the inlet  238  is located adjacent the first end  226  of the structure. In addition, the outlet  240  is located on one side of a centerline C-C of the decorative structure  212 , while the inlet  238  is located on the other side the centerline C-C of the structure. The relative locations of the structure inlet  238  and the structure outlet  240  create the diagonal circulation of water flow within the aquarium  20  that reduces the occurrence of stagnant water regions.  
      In particular, the relative locations of the inlet  238  and the outlet  240  are such that each of the inlet  238  and outlet  240  are positioned a vertical distance D 1 ′ and a horizontal distance D 2 ′ from one another. Preferably, the horizontal distance D 2 ′ is at least half as great as the vertical distance D 1 ′ (each of the distances being defined between centerlines of the inlet and outlet structures). The relative positioning of the structure inlet and outlet  238 ,  240  generates a side-to-side flow component that creates the diagonal circulation of aquarium water to reduce stagnant regions within the aquarium.  
      Similar to the previous embodiments, the decorative structure  212  has a width W 1 ′ ( FIG. 19 ) that is at least 25% of the width W 2  ( FIG. 1 ) of the aquarium  20 . In the illustrated embodiment, the width W 1 ′ of the structure  212  is designed to span a majority of the width W 2  of the aquarium  20 , and may even span the entire width W 2  of the aquarium  20  depending upon the size of the aquarium.  
      Referring back to  FIG. 18 , the heater  216  is positioned in close proximity to the filter assembly  214  so that water flowing into the filter assembly  214  is heated immediately prior to entering the filter assembly inlet  258 . In operation, water is drawn through the plurality of openings  244 , across a heating element  248  of the heater  216 , and into the filter assembly inlet  258 .  
      As can be seen in  FIG. 16 , the decorative structure  212  conceals the filter assembly  214  and heater  216  to enhance the appearance of the aquarium  20 . While hidden from view, the filter assembly  214  and heater  216  are still easily accessible as previously described.  
      Also similar to the previous embodiments, the filter assembly  214  is typically mounted to the edge  64  of the aquarium  20  by a bracket (not shown). The structure  212  of the arrangement  10  is preferably sized such that the filter assembly outlet  260  is located at or adjacent to the water circulation outlet  240  when the filter assembly  214  is mounted to the edge  64  of the aquarium  20 . The heater  216  may be mounted to the filter assembly  214 , to the structure  212 , to the aquarium edge  64 , or to a divider wall  274  as shown in  FIG. 18 .  
      Referring now to  FIGS. 16 and 19 , the arrangement  200  can further include an aeration device  280 . In the illustrated arrangement  200 , the aeration device  280  includes an air stone  282  interconnected to an airline  284 . The airline  284  extends into the cavity  232  of the structure and through an opening  287  formed in the bottom edge of the decorative structure  212 . The air stone  282  is porous to permit air from the airline  284  to bubble out of the air stone  282 . In the illustrated embodiment of  FIGS. 14-19 , the air stone  282  is positioned at the front side  222  of decorative structure  212 . During operation of the aeration device  280 , air bubbles up the front side  222  of the structure  212  to add further interest to the aesthetic appeal of aquarium arrangement  200  while oxygenating the aquarium water.  
      Referring now to  FIGS. 20-24 , a fourth embodiment of an aquarium decor arrangement  300  is illustrated. In this embodiment, the aquarium arrangement  300  also includes a decorative structure  312 , a filter assembly  314 , and a heater  316 .  
      Referring to  FIGS. 20 and 21 , the decorative structure  312  of the arrangement  300  has a front side or surface  322  and a back side or surface  324 . The front side  322  typically includes features or structures  318  designed to make the aquarium&#39;s appearance more natural, beautiful, and enjoyable. The decorative structure  312  has a first end  326  ( FIG. 21 ) and a second end  328 . When positioned within an aquarium  20  ( FIG. 1 ), preferably the first end  326  of the structure  312  rests upon the bottom  30  ( FIG. 1 ) of the aquarium  20 . The second end  328  of the structure  312  is preferably located above the waterline of the aquarium  20  ( FIG. 1 ) when the first end  326  of the structure  312  rests upon the bottom  30 .  
      In use, the aquarium decor arrangement  300  of the present disclosure is self-standing or self-stabilizing. That is, the arrangement  300  rests upon the bottom  30  of the aquarium without the need for additional securing devices, such as brackets or ties. Each of the filter assembly  314  and the heater  316  mount to or are secured to the decorative structure  312  of the arrangement  300 . Therefore, no additional securing devices are needed for these hidden components either. This feature provides a user with greater flexibility in placing and positioning the arrangement within the aquarium so that a variety of aquatic scenes or environments can be created.  
      In the illustrated embodiment of  FIG. 21 , a back panel  325  is located at the back side  324  of the decorative structure  312 . The back panel  325  extends between opposing first and second side walls  346 ,  347  of the decorative structure  312 . The back side  324  of the decorative structure  312  and the back panel  325  define a volume or cavity  332  that is separate from the primary volume  34  ( FIG. 1 ) of the aquarium  20 . In the previous embodiments, the back wall  21  of the aquarium  20  essentially functioned as a back panel to define the cavity. In this embodiment, however, the back panel  325  is provided as a component of the arrangement  300  for use in applications where an enclosed cavity is desired. For example, in some aquarium set-ups, the user may want to position the aquarium decor arrangement at an angle relative to the back wall  21  of the aquarium  20 , as opposed to positioning the arrangement flush with the back wall  21 . Because the cavity  332  of the embodiment of  FIGS. 21-24  is enclosed, the arrangement  300  can be angled relative to the back wall  21  of the aquarium  20 , thereby offering greater flexibility in arranging or designing aquarium scenes.  
      Still referring to  FIG. 21 , a top opening  336  at the second end  328  of the structure  312  provides access to the cavity  332 . Similar to the previous embodiments, the cavity  332  is configured to conceal the filter assembly  314  and the heater  316  when positioned within the cavity, while still providing easy access to the components located therein.  
      Referring now to  FIG. 24 , the decorative structure  12  defines a water circulation inlet  338  and a water circulation outlet  340 . The inlet  338  provides fluid communication from the primary volume  34  of the aquarium  20  to the cavity  332  of the structure  312 . The outlet  340  provides fluid communication from the cavity  332  of the structure  312  to the primary volume  34  of the aquarium  20 . The outlet  340  of the structure  312  is generally a location  372  ( FIG. 23 ) at which water exits the decorative structure  312 . In other words, the outlet  340  typically is defined by the location  372  at which the filter assembly  314  is positioned, and does not require a particular structurally-defined outlet.  
      In each of the illustrated embodiments presently disclosed, the water circulation inlet or inlets and the water circulation outlet are offset from one another such that water flows within the cavity in a direction that is non-opposing to any other water flow direction. This feature creates the diagonal circulation within the cavity (e.g.,  32 ,  132 ,  232 ,  332 ) of the structure, and within the primary volume  34  of the aquarium  20 . In other words, the outlet (e.g.,  40 ,  140 ,  240 ,  340 ) is offset at a location from all inlet structures (e.g.,  38 ,  138 ,  238 ,  338 ) such that an overall diagonal flow pattern is created from the inlet to the outlet. In contrast, the outlets of conventional arrangements are typically located between and above a number of inlets or openings such that water enters the arrangement from all directions and flows toward the outlet from opposing directions. The opposing horizontal flow vectors of this water flow essentially cancel one another so that the overall aquarium flow pattern created by such an arrangement is an up and down flow pattern.  
       FIG. 22  illustrates the water flow pattern (represented by arrows B and C) of the decor arrangement  300 . As shown, all water entering the cavity  332  of the structure  312  flows in a direction that is non-opposed by any other water flow. As previously described, the non-opposed side-to-side flow component of the water flow (shown by arrows B and provided by the horizontal vector of arrows C) creates the diagonal circulation within the aquarium. The diagonal circulation captures and draws a greater percentage of water within its flow, as compared to conventional arrangements, to reduce stagnant water regions within the aquarium.  
      Referring back to  FIG. 24 , the inlet  338  of the structure  312  includes at least one opening, preferably a plurality of openings  344 , formed in the decorative structure  312 . In the illustrated embodiment, the plurality of openings  344  is defined by a grill piece  342  inserted within a notch  366  ( FIGS. 20 and 21 ) formed in the first side wall  346 . The notch  366 , which defines the inlet  338 , and the outlet  340  of the structure  312  are dimensionally located relative to one another as described with respect to  FIG. 7  (e.g. D 1  and D 2 ) to create the diagonal circulation of water flow within the aquarium  20  as shown in  FIGS. 1 and 5 .  
      Referring again to  FIG. 22 , the filter assembly  314  generally includes a submersible pump  378  and a filter housing  354 . The submersible pump  378  defines the filter assembly inlet, and the filter housing  354  defines a filter assembly outlet  360  ( FIG. 23 ). As shown in  FIG. 23 , the filter assembly outlet  360  in the illustrated embodiment is a spillway  368 .  
      The location  372  at which the spillway  368  is positioned at least partially defines the outlet  340  of the decorative structure  312 . The outlet  340  is also partially defined by a recessed lip  350  ( FIG. 20 ) formed along a top edge  352  of the decorative structure  312 ; although no particular structurally-defined outlet is required by the present disclosure. The lip  350  is sized to accommodate the spillway  368  of the filter assembly  314 . In an alternative embodiment, the recessed lip  350  of the structure  312  may itself define the spillway that dispenses water back into the aquarium while the filter assembly  314  may simply direct the flow of filtered water onto the spillway of the structure  312 .  
      In the illustrated embodiment of  FIGS. 20-24 , the recessed lip  350  is sized and constructed to support the entire filter assembly  314  without use of additional brackets. In particular, the spillway  368  of the filter assembly  314  simply rests or is captured within the recessed lip  350  of the structure  312 , while the remaining filter housing  354  and the pump  378  depend downward into the cavity  332 . This mounting arrangement simplifies maintenance of the filter assembly  314  whereby a user need only lift the filter assembly  314  from the recessed lip  350  or set the filter assembly  314  within the recessed lip  350  to detach the filter assembly  314  from or attach the filter assembly to the structure  312 .  
      In other words, the filter assembly  314  is a drop-in or self-contained filter assembly that can be removed from the cavity  332  of the structure for maintenance or other purposes. What is meant by self-contained is that the entire filter assembly, i.e., the submersible pump  378 , the filter housing  354 , and a filter cartridge  333  positionable with the filter housing are part of a replaceable unit that is separate from the structure  312 . The present mounting arrangement also simplifies maintenance of the filter assembly  314  whereby a user can easily access the filter cartridge  333  ( FIG. 20 ) of the filter assembly for periodic maintenance through the top opening  326  of the structure  312  without reaching into the aquarium water.  
      In an alternative embodiment, the filter assembly  314  may simply rest upon a cavity floor  331  ( FIG. 22 ) such that the spillway  368  of the filter assembly  314  is located generally within the recessed lip  350  of the structure  312 . In yet another alternative embodiment, the filter assembly  314  may be mounted to the back panel  325  of the arrangement  300 .  
      Still referring to  FIG. 22 , the filter assembly  314  is positioned within the cavity  332  to maximize a distance D 4  between the filter assembly  314  and the structure inlet  338 . In one embodiment, the distance D 4  between a centerline of the filter assembly inlet formed in the submersible pump  378  and the structure inlet  338  is between about 3.5 and 5.5 inches; although the disclosed principles can be applied in a variety of sizes and applications. Maximizing the distance between the filter assembly  314  and the structure inlet  338  increases the water flow velocity and contributes to the momentum of the side-to-side flow component and the diagonal circulation ( FIG. 1 ) within the aquarium.  
      Referring now to  FIGS. 22 and 24 , the openings  344  of the structure inlet  338  and the heater  316  are arranged such that water flowing through the inlet  338  is in thermal communication with the heater  316 . In particular, the openings  344  are located so that a significant majority of the water flow passes across a heating element  348  of the heater  316  prior to filtration. In the illustrated embodiment, the openings  344  are arranged in a generally vertical array to correspond to the elongated construction of the heater element  348 . In operation, water is drawn through the plurality of openings  344 , across the heating element  348 , and into the filter assembly  314 .  
      As shown in  FIG. 22 , the heating element  348  of the heater  316  is positioned proximate to the pump  378  of the filter assembly  314  so that water flowing into the filter assembly  14  is heated prior to entering the filter assembly inlet. That is, the heater  316  is positioned within the flow pathway, within the cavity  332 , between the inlet  338  and the outlet  340  of the structure  312 . Preferably the heating element  348  is located a distance D 5  of no more than about 5.0 inches; more preferably, no more than about 4.0 inches from the centerline of the filter assembly inlet of the pump  378 . By positioning the heater  316  and the filter assembly  314  in the proximate relative locations, both heated and filtered water is returned to the primary volume  34  of the aquarium  20  during operation. By returning heated, filtered water to the aquarium, and creating a diagonal circulation within the aquarium, the heated, filtered water is better dispersed within the aquarium to provide a more uniform temperature throughout the aquarium.  
      In the illustrated embodiment, the heater  316  is mounted to a bracket  327  located within the cavity  332  of the structure  312 . The bracket  327  is secured to an inner side  329  of the first side wall  346  of the structure  312 . Preferably, the bracket positions the heater  316  so that controls of the heater can be easily accessed through the top opening  336  of the cavity  332 , while the heating element  348  is located between the structure inlet  338  and the filter assembly inlet of the pump  378 , as previously described.  
      Referring back to  FIG. 21 , the arrangement  300  can further include an aeration device  380 . In the illustrated embodiment, the aeration device  380  includes an air stone  382  interconnected to an airline  384 . The airline  384  extends into the cavity  332  of the structure and through an opening  386  formed adjacent to the first end  326  of the structure  312 . The air stone  382  is porous to permit air from the airline  384  to bubble out of the air stone  382 . During operation of the aeration device  380 , air bubbles up the front side  322  of the structure  312  to add further interest to the aesthetic appeal of aquarium arrangement  300  while oxygenating the aquarium water.  
      The above specification provides a complete description of the present invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, certain aspects of the invention reside in the claims hereinafter appended.