Aquaforest TestPro Alkalinity is designed to quickly measure Carbonate Hardness(dKH) and Alkalinity(meq /L) in marine water. Alkalinity levels should be analysed regularly, together with other critical water parameters like Calcium and Magnesium. Recommended Carbonate Hardness level: 6.5 – 8.0 dKH. Test Kit contains sufficient reagents to perform approx. 78-100 separate tests within that range.