Only fits for 6Watt 500L / h 4-in-1 Internal Aquarium Filter
Biochemical-sponge can effectively filter waste and improve the circulation system to maintain a clean water environment.
Replace or clean filter sponge every two weeks or sooner for optimal performance.
Easy to seperate and clean,absorbs odors and discoloration,provide a healthy water for your aquarium
Included 4Pcs Biochemical-sponge only