Abstract: An animal habitat arrangeable in a vertical or a horizontal orientation comprising a rectangular enclosure having four side-walls and two opposing end-walls, wherein the four side-walls are joined to a frame at a first end of the enclosure; and the two opposing end-walls comprise a first end-wall and a second-end wall; wherein the first end-wall is releasably connectable to the frame, positionable within the frame in a plurality of orientations and provides an end-wall door with access to an interior of the rectangular enclosure; wherein at least one of the side-walls provides a side-wall door with access to the interior of the rectangular enclosure and has a hinge position which is changeable along opposite side-walls of the enclosure.

Abstract: An animal habitat arrangeable in a vertical or a horizontal orientation comprising a rectangular enclosure having four side-walls and two opposing end-walls, wherein the four side-walls are joined to a frame at a first end of the enclosure; and the two opposing end-walls comprise a first end-wall and a second-end wall; wherein the first end-wall is releasably connectable to the frame, positionable within the frame in a plurality of orientations and provides an end-wall door with access to an interior of the rectangular enclosure; wherein at least one of the side-walls provides a side-wall door with access to the interior of the rectangular enclosure and has a hinge position which is changeable along opposite side-walls of the enclosure.

Abstract: Disclosed herein are wedge-shaped filter cartridges having a maximized upstream surface area. The filter cartridges are modular and may be stacked in a filter cartridge system.

Abstract: Disclosed are filter assemblies for an aquarium tank. The disclosed assemblies include a filter basket assembly in which one or more filter baskets are connected, either directly or indirectly, to a filter pump basket. The filter pump basket typically is located upstream of the one or more filter baskets and pumps water upwards through the filter basket assembly.

Abstract: Disclosed herein are wedge-shaped filter cartridges having a maximized upstream surface area. The filter cartridges are modular and may be stacked in a filter cartridge system.

Abstract: Disclosed are fish food dispensers for aquariums, which are automatic and may be utilized to feed fish in the absence of the aquarist. The dispensers typically utilize a replaceable fish food container.

Abstract: Disclosed are vertical sock filters for aquarium filter assemblies. The sock filters typically include an annular collar coupled to filter material. The filter material typically is a composite material that includes upper material and lower material, where the upper material typically is more porous than the lower material. The assembly and the annular collar may include respective first and second coacting components that mate or interlock with each other.

Abstract: Disclosed are filter assemblies for an aquarium tank. The disclosed assemblies include a filter basket assembly in which one or more filter baskets are connected, either directly or indirectly, to a filter pump basket. The filter pump basket typically is located upstream of the one or more filter baskets and pumps water upwards through the filter basket assembly.