The AquaClear Quick Filter attachment converts AquaClear Powerheads into powerful filters for rapid removal of most particulate waste. The large Quick Filter is ideal when providing extra circulation to protect fish and invertebrates. 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. Clip two or more Quick Filters together for expanded filtering capacity or for deeper aquariums. The AquaClear Quick Filter fits all AquaClear Powerheads.