The Seachem Reef Status Magnesium kit is capable of at least 75 tests for magnesium. It is designed specifically for seawater. The test is based on titration of magnesium with EDTA in the presence of a magnesium specific indicator dye after the coprecipitation of calcium and strontium. Natural seawater concentration for magnesium is approximately 1,300 mg/L. The magnesium concentration in kalkwasser treated aquaria may be as low as 600 – 700 mg/L. In general, it is prudent to maintain magnesium concentrations in reef aquaria between 1,200–1,400 mg/L. If magnesium levels are found to be deficient, Seachem recommends the use of Reef Advantage Magnesium (ammonia free! unlike competing liquid magnesium supplements). Seachem also offers other reef specific test kits: Reef Status: Strontium, Reef Status: Calcium and MultiTest: Reef Special (tests for phosphate, silicate and iodide).
Natural seawater has a total alkalinity of about 2.5 meq/L, of which about 0.1 – 0.2 meq/L is from borate. In an aquarium, it is advantageous for both pH control and improved calcium stability to have a higher borate content. This, however, should not be at the expense of carbonate. It is useful, then, to maintain a total alkalinity of about 4 – 5 meq/L with a borate component of about 1.5 – 2.0 meq/L. This kit is capable of at least 75 tests for total alkalinity, borate alkalinity, and carbonate alkalinity. It is designed specifically for seawater. The test is based on titration of carbonate and/or borate with acid in the presence of a pH indicator dye (endpoint = pH 4 for total alkalinity and endpoint = pH 6 for borate alkalinity). If alkalinity levels are found to be deficient, Seachem recommends the use of Reef Builder (powder) or Reef Carbonate (liquid) to restore depleted alkalinity levels. To restore depleted borate alkalinity use Marine Buffer on a regular basis or use Seachem’s Reef Salt with your next water change.
The proper performance of this kit may be validated by running a test in the normal manner except that the reference sample is used in place of an aquarium sample. It is not necessary to run a reference test to use the Seachem Reef Status Magnesium kit. The only time you might choose to run a reference test is if you have cause to believe the test is giving incorrect results. If you run a test using the reference sample and obtain the correct result (based on the known reference value provided) then you know the test is giving correct results. To run a reference test use the Magnesium Reference as the sample. Reference value is listed on the container label.
More information about the Seachem Reef Status Magnesium here