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Hang In/Hang On Tank counter current protein skimmers were the first type of skimmers to appear in the saltwater aquarium hobby. They were simple devices which used an air pump driven air stone, the bubbles from which collected proteins and deposited them in a collection cup. These skimmers are the least expensive and the easiest to install and operate. With in-tank skimmers, there are no worries about wet floors.
AQUATICLIFE 115 Mini Internal Protein Skimmer/Filter
The Internal Mini Skimmer 115 measures only 3" x 3-1/4" x 10-1/2" high to provide supplemental filtration in saltwater aquariums up to 30 gallons. This compact skimmer is driven by an 8-watt needle-wheel impeller pump for energy efficiency AND effective organic waste removal. Mounting bracket and suction cups included for convenient placement and quiet operation inside your aquarium.
Red Sea Fish Pharm Ltd. PRIZM HANG ON SKIMMER
Compact size, powerful pump, and easy "hang-and-go" setup make it a great choice for the small-to-medium home aquarium. Features an 18-blade Turbo-Jet Air Impeller that quietly generates a constant stream of microbubbles in a homogeneous air/water mixture. Patented, 2-stage reaction chamber extends contact time while providing both co- and counter-current action, creating a protein-rich, stable foam. Requires 2" of headroom for removable 17 oz. collection cup. Includes adjustable height surface skimmer, filtration media basket, and carbon. For larger aquariums, use the Prizm Pro Deluxe (13" x 20" high x 3-1/2" deep). Includes removable 40 oz. collection cup and an optional drainage port.
Instant Ocean SeaClone Protein Skimmer
The SeaClone Protein Skimmer can be hung on your aquarium or placed in your sump. The SeaClone's built-in Maxi-Jet 1200 Pump creates a froth of micro-bubbles created by the venturi action. Water and air swirl together in tornado-like motion in the Vortex chamber, drawing out dissolved wastes. The adjustable water flow and air injection rate means precise control and reliable performance. Convenient design for easier cleaning and maintenance. The SeaClone Protein Skimmer is available in two sizes: SCPS 100 for marine aquariums up to 100 gallons (3-1/2" diameter x 18" high) and SCPS 150 for marine aquariums up to 150 gallons (3-1/2" diameter x 25" high).
Danner Skilter 400 Power Filter for Aquarium
Maintenance-free Skilter Filter offers total, efficient filtration for saltwater aquariums. Combines chemical, mechanical, and biological filtration techniques with protein skimming. Makes an ideal primary filter for 10-55 gallon saltwater and mini-reef aquariums. The advanced venturi-type protein skimmer of the Skilter Filter can also be used as a supplementary filtration device for aquariums up to 100 gallons. This filter hangs on the back of the aquarium.
Turboflotor Hang On Protein Skimmer Reef Aquarium Filter
Turboflotor 1000 Multi measures 7-1/2" x 15" x 21-1/4" high and includes a pump and fittings. This versatile unit can be used as a hang-on style or placed inside or outside of the sump. Only the water supply pump needs to be placed in the aquarium or sump. Two outflow boxes direct water back to the aquarium or sump. For aquariums up to 250 gallons.