Bio Ceramic Rings are a convenient ready-to-use nylon mesh filter bag filled with Ceramic Rings. Surface area and pores sized to accommodate bacteria necessary for biological balance and to remove toxic Ammonia and Nitrite. * Helps remove toxic Ammonia and Nitrite. * Surface area and pores sized to accommodate bacteria necessary for biological balance. * The Bio Ceramic Rings produce crystal clear water and is perfect for use in any canister filter. * Net bag included.