The Salifert magnesium test is very straightforward and does not suffer from calcium and strontium interferences when within certain bounds. It measures in sufficient accurate steps of 30 mg/L with a sharp color change. The kit can perform approx. 50 measurements.

Magnesium is present in NSW in a fairly high concentration (1300 - 1400 mg/L). Magnesium is an essential part of chlorophyll, which is necessary for photosynthesis. Without photosynthesis, plants such as algae and corals would not be able to live.

Magnesium has another important function in maintaining the correct combination of calcium concentration and alkalinity or carbonate hardness possible.

Maintaining a correct magnesium concentration is therefore very important and is indirectly responsible for fast coral and calcareous algae growth by virtue of making the maintenance of correct calcium and alkalinity figures possible.

The Salifert liquid-magnesium additive does not imbalance the system and is ultra pure. Salifert was the first in offering such an additive. A more economical version suitable for a one time major correction is the Salifert Magnesium-powder.