Aquaforest TestPro Calcium is designed to quickly measure the concentration of Calcium in marine water. Calcium plays an important role in many biological processes, e.g. takes part in the construction of hard coral’s calcium carbonate skeleton. Calcium levels should be analysed regularly, together with other critical water parameters like Alkalinity and Magnesium. Recommended Calcium level should be maintained in the range between 400-450 mg/l (ppm). Test Kit contains sufficient reagents to perform approx. 55-60 separate tests within that range.