The Waterbox Magnesium Test Kit offers fast, reliable testing to determine the magnesium (Mg) concentration in saltwater aquariums. Magnesium is a core element in reef chemistry, supporting coral skeletal growth and helping maintain overall stability in the system. It plays a major role in balancing calcium and alkalinity, and its presence helps reduce unwanted calcium carbonate deposits on pumps, heaters, and other equipment.

Consistently maintaining magnesium within the natural seawater range of 1200–1400 ppm is essential for healthy coral development and for keeping other key parameters in check. Regular testing alongside alkalinity and calcium helps maintain a balanced and thriving environment.

Each kit provides enough reagents for roughly 55–60 individual tests.