The AquaClear Quick Filter Powerhead attachment converts AquaClear Powerheads into powerful filters for rapid removal of most particulate waste. The extra large central core holds an ample supply of granular filter material like carbon, for specialized jobs such as the removal of liquefied waste or polishing aquarium water. The Quick Filter is also ideal when you need extra circulation to protect fish and invertebrates. Clip two or more Quick Filters together for expanded filtering capacity or for deeper aquariums. Safe for fresh and saltwater aquariums, Quick Filter is exclusively designed to fit AquaClear Powerhead Models 10, 20, 30, 50 and 70.