1. 8Layer Filter Pads with Super Filtering Effect: Our filter pad for aquarium has 8 filter media, nanobiosponge filters, fiber bio sponge filters, two layers of 3dimensional mesh cloth, two layers of ultrahigh precision cloth and two layers of activated carbon cotton. It will trap larger particles and fine particles and will filter out very fine impurities and germs. 2. Highquality and Super Durability: The aquarium filter pad is made of durable nano bio sponge filter and fiber bio sponge filter, and then fixed by two layers of ultra high precision cloth, and finally two layers of threedimensional mesh cloth are glued and molded with highstrength environmentally friendly resin. This aquarium filter floss uses dense structural media, which are very durable and easy to clean, and is more durable than traditional filter cotton. 3. Standard Size: It is 19.3 in × 15.7 in × 0.8 in thick aquarium filter media. 4. Wide Application Range: Our 8layer aquarium filter is very suitable for freshwater or saltwater aquariums. This aquarium filter floss can be used as a fish tank accessory, prefilter for wet/dry filters, sewage tanks, tank filters, reef tanks, ponds, fish and vegetable symbiosis systems etc. If you are annoyed that the water in fish tanks turns yellow, it is absolutely a perfect choice for you.