This Bio-Chemical Mat filter has a different mesh, with high resilience, many colors, and good air permeability. It is durable in water and low cost. The application and action of the filter sponge. This product can be used for seawater and freshwater tank,s and waterweeds tanks with the sizes being cut as your wish. According to the analysis of the experts, this product is very suitable for the breeding of nitrobacteria. The biochemical sponge has the best effect on decomposing the excrement and the forage leftovers and improving the filtering effect, It can reduce the death rate of fish. Being cleaned with water once per month, it can be reused after cleaning, not lose shape, and not blocking.