The Penn Plax Cascade Canister Filter Bio-Sponge keeps your aquarium water clean and clear. The Bio-Sponge also extends the life of carbon and biological media by trapping debris that would otherwise soil them.
Optimizes colonization of beneficial aerobic bacteria
Removes ammonia and nitrites keeping the aquarium healthy
Convenient, no fuss, replacement sponge
Sizing: Fits Cascade 1200 and 1500 Canister Filters ONLY.