The API KH Carbonate Hardness Test Kit uses a drop method to test the Carbonate Hardness (KH). Carbonate Hardness is the measurement of dissolved carbonate and bicarbonate ion concentrations. when the KH is to low, the ph level can often shift, causing the tank to stress. To test your water, add about 5ml of water to the test tube, add one drop at a time, and note when the water begins to change color. Comes with test fluid, test tube, and detailed instructions.
