Hagen Aquaclear Power Filter'sPatented Refiltration System provides optimal mechanical, chemical and biological filtration for 5 - 110 U.S. Gal. Aquariums.
For Flow Control Simply shift the patented "Flow Adjustment Control" at the the intake siphon. When the "Flow Adjustment Control" is at its greatest blockage, AquaClear's input and exhaust volumes are approximately a third of its maximum capacity.