Product name：AZOO 3 IN 1 BIO-SPONGE x2 Biological filter material
1. AZOO 3 IN 1 BIO-SPONGE contains three bio-sponges with different density-low in blue,middle in brown and high in black. The AZOO 3 IN1 BIO-SPONGE can proceed aerobic bacteria's nitrification and anaerobic bacteria's denitrification at the same time.
2. Its multi-porous feature will avoid blockages and provide the largest adhesion area for bacteria.
3. The blue and brown sponges with loose pores can generate spiral water flow to provide the most dissolved oxygen to for the growth of aerobic nitrifying bacteria.
4. The denser black bio-sponge is suitable for the growth of anaerobic denitrifying bacteria.
5. It is made of high quality materials to justify its durable. Meanwhile, it also can be cut into different sizes as you need. It is the best biological filter material.