Aquarium Solutions Bacto-Surge Biological Sponge Filter Black XL
- Highly porous sponge maximizes bacterial action
- Increased surface area offers maximum bacteria colonization
- Soft sponge material is easily cleaned
- Polyether foam for longer life
- Uplift tube and air diffuser combination provide maximum lift and won't easily clog
- Other uses: polishing filter for canister filter applications, hang on filter applications or uplift tubes of undergravel filters