Product description: 1. This product is suitable for freshwater, seawater, water plants cylinder, the size of the free carriers can be cut. 2. Dense hole clearance and flexibility, is most suitable for analysis by experts pay Nitrifier the hotbed. 3. Biochemical cotton waste and feed residues to decompose, improve water filter cleaning, the best results. 4. Washed with water once a month, is not blocked, the same type, after cleaning reusable.