Reef-Basis Magnesium is a high quality, ionically balanced solution of hydrated magnesium salts designed to safely raise the magnesium level in marine aquariums, providing essential magnesium for support of aragonite formation in corals, assisting in regulation of calcium and alkalinity levels and for other desirable functions. It contains no acetate, gluconates, polygluconates or other unnecessary organics to pollute your aquarium. It is phosphate and nitrate free.

Proper control of magnesium level is imperative for the health and growth of corals as well as maintenance of calcium and buffer levels. Some sea salt mixes are low in magnesium.