Fluval Biomax bui rings have a complex pore system where beneficial bacteria can thrive. Biomax bio rings allow ideal water movement throughout the media, to ensure optimal contact time for efficient biological filtration. 500g.

For freshwater and marine environments.

For filter models: 106, 206, 306, 406, FX5, 105, 205, 305, 405, 104, 204, 304, 404.