Drawstring Aquarium Fish Tank Sock Filtration Marine Sump Filter Cotton Bag Cleaner Practical Description: Filter bag provides excellent mechanical filtration that can help reduce the amount of reef and other substances thoroughly in your aquarium, which is an essential part to keeping aquarium water clear and clean. Features: Made of filter cotton material, which is soft, durable,  and with high density. Wetland water purification principle is applied to block the dirt, obstacles, and other substances to prevent bacterial growth. Back with knitted construction makes it breathable, water pervious, so as not to block the flow of water. Fiber fine, which can be very effective filtering impurities in water. Convenient cleaning, machine washable, no deformation. Perfect for fresh water fish and sea water fish. Specifications: Material: Filter Cotton Color: White Size: Approx. 35 * 20cm / 13.8 * 7.9inch Package Weight: Approx. 64g Item Type: Aquarium Filter  Function: Filtering Impurities In Water Package Include: 1 x Aquarium Filter Bag Only