The Role Of Magnesium In Marine Aquarium Chemistry

By Than Thein

One of the big differences in moving from freshwater systems to saltwater systems is a greater emphasis on water chemistry. There is a pretty steep learning curve to get a handle on all the different chemical parameters, and it can be a source of frustration for many aspiring reef hobbyists. In aquariums with an abundance of stony corals, the levels of calcium, alkalinity, and magnesium are important to monitor. This article will focus on magnesium, an important but often overlooked ion in reef chemistry.

What is the role of magnesium in the reef aquarium? First off, it is the third most abundant ion in salt water. The two most abundant ions, for those that are curious, are sodium and chloride. That should come as no surprise, as sodium and chloride make up table salt and give saltwater its characteristic taste.

Magnesium, like most other ions in salt water, is measured in parts per million (ppm). Parts per million is a slightly deceptive sounding unit of measurement. It is a mass ratio rather than an exact count …read more

Read more here: Saltwater Smarts