Hydor Activated Carbon Salt Water Professional External Canister Filter Media – Low Ash Content For Saltwater Aquariums – Produces Crystal Clear Water – Includes Mesh Bag – 400 Gm Pouch, Black (D02200)

Highly adsorbent Saltwater activated carbon eliminates bad odors and polluting substances. 400gm pouch. Carbon can be substituted by Zeolite which is used in some marine aquaria to keep nutrient concentrations low for the benefit of corals adapted to waters.