Koralia 1 Circulation Pump for marine and fresh water aquariums is designed to be super efficient and long-lasting with very low energy consumption compared to traditional circulation pumps. Koralia’s water flow is both powerful and delicate making it ideal for marine and reef tanks. The unique patented magnetic support allows free and secure positioning anywhere in aquariums with glass up to 15 mm (0,6 in) thick. The special sphere shaped connection makes flow directing quick, simple and fully adjustable. Koralia 1: 400 gph; 4 w; for fresh water aquariums 25 to 45 gal or marine aquariums 15 to 25 gal. Aquarium sizes are suggested by Hydor. Each hobbyist should choose the Koralia model that better suits the needs of the inhabitants (plants, fish, corals, etc.) of the aquarium in which the pumps will operate. Shipping weight: 1 1/2 lbs.