Aquarium biochemical filter replacement sponge Easy to install and disassemble, and convenient to clean Wide range of applications, suitable for saltwater tanks, freshwater tanks, and algae tanks, etc Efficient bacteria cultivation. Made of sponge with wrinkles, increasing the number of filter layers and having good filtering effect Restore natural ecological water quality Remove odors, adsorb impurities. Simple to operate. Deodorize and activate water Customizable in size, color, style and material