Cascade Hang On Filter 300 Bio-Sponge

Penn Plax Cascade 300 GPH Bio Sponge Replacement Bio Sponge for the Cascade Hang On 300 power filters. Penn Plax Cascade 300 GHP Bio Sponge is ideal for housing beneficial bacteria for superior biological filtration. Product Features Replacement Bio Sponge Suits Cascade Hang On 300 power filters Grows beneficial bacteria for superior biological filtration Contains 2 replacement sponges Shop more aquarium filter media and parts here.