Abstract: A basking heater for an animal, such as a reptile, includes a housing, a heating element within the housing, and an opening in a bottom of the housing, so that the heating element may radiate heat through the opening, and an attachment arrangement. The attachment arrangement can be used to selectively attach the heater to a terrarium. The housing can be made of thermal plastic resin and can include vents for cooling the housing. The housing can have low profile shape. The heater may have multiple power settings.

Abstract: An aquarium filter cartridge includes a frame and a media pack attached to the frame. The frame includes recessed sections along the sides. The filter cartridge can be part of dual filter cartridge, also including a biological host media filter element. The filter cartridge or the dual filter cartridge can be mounted in a filter housing by sliding within receiving grooves in the filter housing. Methods of servicing are included.

Abstract: An aquarium filter cartridge includes a frame and a media pack attached to the frame. The frame includes recessed sections along the sides. The filter cartridge can be part of dual filter cartridge, also including a biological host media filter element. The filter cartridge or the dual filter cartridge can be mounted in a filter housing by sliding within receiving grooves in the filter housing. Methods of servicing are included.

Abstract: An aquarium filter cartridge includes a frame and a media pack attached to the frame. The frame includes recessed sections along the sides. The filter cartridge can be part of dual filter cartridge, also including a biological host media filter element. The filter cartridge or the dual filter cartridge can be mounted in a filter housing by sliding within receiving grooves in the filter housing. Methods of servicing are included.

Abstract: A basking heater for an animal, such as a reptile, includes a housing, a heating element within the housing, and an opening in a bottom of the housing, so that the heating element may radiate heat through the opening, and an attachment arrangement. The attachment arrangement can be used to selectively attach the heater to a terrarium. The housing can be made of thermal plastic resin and can include vents for cooling the housing. The housing can have low profile shape. The heater may have multiple power settings.

Abstract: An aquarium filter cartridge includes a frame and a media pack attached to the frame. The frame includes recessed sections along the sides. The filter cartridge can be part of dual filter cartridge, also including a biological host media filter element. The filter cartridge or the dual filter cartridge can be mounted in a filter housing by sliding within receiving grooves in the filter housing. Methods of servicing are included.

Abstract: A protein skimmer having a water column chamber and a fixed deflector. The fixed deflector including a plurality of blades that impart a swirling action on water flowing through the deflector. The deflector further providing an even distribution of bubbles within the water column chamber during protein filtering operation. The deflector including a central hub that aids in maintaining the velocity of water flowing through the deflector.

Abstract: A filter cartridge including a filtering body having first and second porous filter walls. The second porous filter wall having a density that is different than the first porous filter wall. The density of the second porous filter wall being defined by interstitial spaces. The filter cartridge further including discrete chemically filtering particles that are captured within the interstitial spaces of the second porous filter wall when the filtering body is in a vertical filtering orientation.

Abstract: A protein skimmer having a water column chamber and a fixed deflector. The fixed deflector including a plurality of blades that impart a swirling action on water flowing through the deflector. The deflector further providing an even distribution of bubbles within the water column chamber during protein filtering operation. The deflector including a central hub that aids in maintaining the velocity of water flowing through the deflector.

Abstract: A sump arrangement for use with an aquarium. The sump arrangement including a dedicated skimmer area that maintains a constant water level to increase operational efficiencies of protein skimmers. The sump arrangement further including a sump tank having an elongated water flow pathway that aspirates air bubbles and improves the clarity of filtered water returning to the aquarium.

Abstract: A filter cartridge including a filtering body having first and second porous filter walls. The second porous filter wall having a density that is different than the first porous filter wall. The density of the second porous filter wall being defined by interstitial spaces. The filter cartridge further including discrete chemically filtering particles that are captured within the interstitial spaces of the second porous filter wall when the filtering body is in a vertical filtering orientation.

Abstract: A filter arrangement for filtration of a primary fluid, the filter arrangement having a filtration region and a bypass region. The bypass region is a sealed region containing a secondary fluid having a specific gravity different than a specific gravity of the primary fluid. The bypass region providing a bypass pathway for flow of the primary fluid during extended use of a clogged filter cartridge.

Abstract: An impeller, and impeller and rotor assembly, for use with a permanent magnet motor that provide uni-directional rotation. The impeller and rotor assembly includes an interconnecting arrangement and a locking arrangement that permit continuous rotation in a first direction and prevent continuous rotation in a second opposite direction.

Abstract: An impeller, and impeller and rotor assembly, for use with a permanent magnet motor that provide uni-directional rotation. The impeller and rotor assembly includes an interconnecting arrangement and a locking arrangement that permit continuous rotation in a first direction and prevent continuous rotation in a second opposite direction.

Abstract: A slip joint for use in a well string and having a removable torque transmitting key. The slip joint includes an outer female mandrel having a central opening therethrough in which is slidingly positioned a male mandrel, also defining a central opening therethrough. In one embodiment, the male mandrel defines at least one longitudinal slot therein and the female mandrel defines a transverse opening therethrough adjacent the slot. The torque transmitting key is positioned in the transverse opening and extends into the slot. In the second embodiment, the inner mandrel includes a flat surface thereon and the outer mandrel has a longitudinal slot therein adjacent the flat surface. The key includes a ring portion having a flat surface therein engageable with a flat surface on the male mandrel and a lug portion extending from the ring portion into the slot.

Abstract: An annulus pressure responsive downhole tool includes a housing with an operating element disposed in the housing. The operating element is movable from a first element position to a second element position relative to the housing. A hydrostatic well annulus pressure referenced annulus pressure responsive first power piston is disposed in the housing and movable from a first to a second position thereof relative to the housing in response to an increase in well annulus pressure. A lower than hydrostatic well annulus pressure referenced annulus pressure responsive second power piston is disposed in the housing and is operatively associated with the operating element for permitting the operating element to move from its first element position to its second element position in response to movement of the second power piston from a first position to a second position thereof relative to the housing.