HOZELOCK cyprio is the brand name. Which model filter are you referring to? Most of their models are configured to have water pumped from the tank/pond to the filter with a gravity outlet back to the tank/pond. Their recommended pumps use alot of power. And, you can't guage pond filter capacity to aquarium applications. For tanks, it's the volume of the bio-chamber that's most important with ~2.2 gallons, of chamber size, per 100 gals of tank with normal bio-mass.