Your underwater companions deserve a clean and fresh aquarium on a daily basis. This is easily achievable with Top Fin's Filter Sponge. This sponge helps trap small particles and encourages beneficial bacteria keeping your aquarium healthy. Your aquatic friends will love swimming, playing, and resting with the comfort of knowing that they're well taken care of. Only at PetSmart. Features: Helps trap small particles not captured by filter pad, Encourages beneficial bacteria Includes: (1) Sponge Intended For: Top Fin Canister Filter Color: Black Size: Available in Medium and Large Instructions: Use 1 Top Fin Filter Pad for the Top Fin Canister Filter. Rinse pad thoroughly before inserting in filter. Place directly into chamber. To help maintain a healthy aquarium, rinse filter pad as needed, and replace every 4-6 weeks. Discard after use. Change out 10% of the water weekly or 25% monthly. Use a water conditioner (sold separately) every time you add fresh tap water to your aquarium. Never use soap, detergents or cleaning agents while cleaning the aquarium or equipment as they can harm your fish. Caution: This is not a toy. Keep out of reach of children. Size: Large.