Features 150 titration tests for calcium Rapid & simple 3 step procedure Sharpest color change endpoint Precise results in 5 mg/L increments Easy test validation with included reference Overview Natural sea water contains between 400 – 410 mg/L of calcium. A healthy reef environment should have between 380 – 420 mg/L of calcium. Levels above 420 mg/L are not beneficial. Levels below 380 mg/L should be corrected as soon as possible. This kit is capable of at least 150 calcium determinations and is designed specifically for seawater. The test is based on titration of calcium with EDTA in the presence of a calcium specific indicator dye after the coprecipitation of magnesium and strontium. Titration Method The test is based on titration of calcium with EDTA in the presence of a calcium specific indicator dye after the coprecipitation of magnesium and strontium. During the testing procedure, the sample transitions between pink and true blue. Once the sample turns blue, the test is complete. Calcium concentration corresponds to markings on the titration syringe.