ME Coral Granular Ferric Oxide 250g
Granular Ferric Oxide (Gfo) is the only chemical utilized by most reefers to reduce Phosphates (PO4). Elevated PO4 levels bring undesirable algae of all types and colors. These high levels are also detrimental to coral growth and color. This is the area that is typically the biggest struggle for many aquarist. Natural Seawater has PO4 levels below .01.