NT Labs MARINE Magnesium Test Kit

Magnesium is the second-most abundant cation found in natural seawater. Magnesium is essential for the efficient assimilation of calcium by marine invertebrates.

Without the correct levels of magnesium, corals and invertebrates cannot properly or efficiently utilise calcium for the formation of their shells and growth of skeletons. Sufficient magnesium also prevents precipitation of calcium and carbonate ions, ensuring bioavailable calcium and a pH stabilising effect.  As magnesium tends to deplete with the age of the water, monitoring the magnesium frequently is the only reliable method to determine the concentration present in the water.

The average magnesium level in natural seawater is 1300-1400 mg/l.  Equally importantly, the correct ratio between magnesium and calcium should be achieved.  The concentration of magnesium should be 3 times that of calcium (e.g. a magnesium to calcium of 3:1).