Descriptions: This product is suitable for seawater, fresh water, water tanks, size can be cut freely. On the biochemical cotton waste and feed residue, improve water quality filter clean. Best effect, reduce the fish mortality. Cleaned once a month, no blocking, no deformation, can be reused after cleaning. On the biochemical cotton waste and feed residue, improve water quality filter clean. Our premium bulk roll is aquatic pet safe and are made without dyes. Premium Filter Pad Provides Proven Superior Mechanical Filtration. Thoroughly Tested on Thousands of Aquariums Our Premium Filter Pads quickly became the top choice for filtration media; they filter large and fine debris from the water and offer consistent and repeatable filtration performance in all types of aquariums. The filter pads are typically used as a pre-filter for wet/dry filters, sumps, and canister filters to clean water in freshwater, saltwater, reef aquariums and other types of fish tanks. They also provide mechanical filtration in aquaponics systems, turtle tanks, terrariums, and much more. It is made of high quality materials to justify its durable. Meanwhile. Can be rinsed off for multiple reuses .it also can be cut into different sizes as you need. It is the best biological filter material. Mechanical Filter Sponge is the first line of defense in removing dirt and floating debris from your terrarium or aquarium. The material has great thickness, it is durable. Regular cleaning! (About 10-20 days to wash) can be reused after cleaning Specifications: Material: Sponge Color: Blue/Yellow Size: 50x50x2cm Quantity: 1 Pc Note: 1.Transition: 1cm=10mm=0.39inch 2.Please allow 0-3cm error due to manual measurement. pls make sure you do not mind before you bid. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! No Retail Package Package includes: 1 Pc x Filter Cotton