Oceanic BioCube Circulation Aquarium PumpThe BioCube Circulation Pump simulates natural river and reef currents by continuously circulating water throughout the aquarium. With a 250 gallon per hour flow rating the BioCube Circulation Pump makes a great addition to any nano reef aquarium. The pump fits all sizes of BioCubes as well as other aquariums 30 gallons and under. Easy-lock suction cup makes installation and adjustments a snap. Energy-efficient motor and impeller increase water movement with less power.