API General & Carbonate Hardness Test Kit

Tests tap water and freshwater aquariums for general hardness(GH), the measure of dissolved calcium and magnesium ion concentrations, and(KH), the measure of dissolved carbonate and bicarbonate ion concentrations, also alkalinity. * For Fresh water * Helps detect stress on fish caused by rapid pH shifts, the result of low levels of KH * Helps aquarists duplicate the natural habitat of their fish, thereby providing a healthy aquarium environment. 2 Bottle Kit.