API GH & KH Test Kit 58 API GH & KH Test Kit for Freshwater 50 Tests Customer Rating  N/A Add Review Ask Question $12.95 Qty : < > Product Description Reviews (0) (View All) Questions (View All) Tests tap water and freshwater aquariums for general hardness (GH) and carbonate hardness (KH). Helps detect stress on fish caused by rapid pH shifts, which result from low KH levels and helps aquarists duplicate the natural habitat of their fish. 50 Tests   Add Review There are no reviews for this product. Ask Question There are no questions asked for this product. Ok