Aqua One 5 in 1 Fresh Water Master Test Kit Water Parameters are essential to maintain a healthy tank for fish and plants. The Aqua One 5 in 1 Test Kits makes all essential tests monitoring easy and accurate. Each kit comes complete to test the 5 essential water parameters to make sure that you can easily maintain a safe and healthy environment in your aquarium or fish tank. Aqua One recommends that you test your water parameters at least once a week. Freshwater kit tests for: pH Ammonia (NH3/NH4) Nitrite (NO2) Nitrate (NO3) Carbonate Hardness (kH) Comes complete to test 5 essential water parameters to help ensure you are maintaining a safe and healthy environment for all of your aquatic inhabitants Performs up to 60 complete tests Read all instructions carefully before use.