API Freshwater Master Test KitAPI Freshwater Master Test Kit This kit tests tap water and aquarium water for five different parameters that affect the health of freshwater fish: pH, High Range pH, Ammonia, Nitrite and Nitrate. Highly accurate and economical. Key Benefits: Unique, transparent dome allows clear view of kit contents Includes all tests required to test the nitrogen cycle Kit includes computer calibrated and laminated colour cards 4 test tubes and holding tray Also