This black bio filter sponge measures 45x45x4.5 cm and is designed to effectively filter out debris and other particles from the water. It is made from a durable and highly absorbent material that traps dirt and debris, while the porous structure allows water to easily flow through. The sponge is also ideal for providing a safe and healthy environment for aquatic life, as it helps to reduce nitrate levels and improve water quality. The filter sponge is easy to clean and maintain, and it can be used in both fresh and saltwater aquariums.