Fluval BIO-FX, Biological Aquarium Filter Media Suitable for Most Aquariums and Filters, 5 Liters

Biological filter media made from safe, inert ceramic material that does not alter water chemistry
Deep pore structure with interconnected micro-tunnels offers vast surface area for biological activity to occur
Linked cavities permit free and even water flow, discourage blockages and prolong contact time for superior and effective biological filtration
Allows for the establishment of a high concentration of biological activity to reduce ammonia and nitrite quickly and efficiently for a healthier aquarium
For best results, rinse monthly using aquarium water and replace partially every 6 months and for optimal filtration, place in the last stage of the filtration process