Contains one (1) API PHOSPHATE TEST KIT 150-Test Freshwater and Saltwater Aquarium Water Test Kit, including 2 bottles of testing solution, 2 color cards and 1 test tube with cap Helps monitor and adjust pH and prevent invisible water problems that can be harmful to fish and corals Reads phosphate levels between 0-10 ppm Prevents excess and unsightly algae which can cause fish stress and inhibit the growth of hard corals Use for weekly monitoring and when water or fish problems appear Keep your fish healthy and thriving by testing your aquarium water's PO4 3- levels regularly with this easy-to-use API PHOSPHATE TEST KIT for freshwater and saltwater aquariums. Testing water parameters weekly helps prevent invisible water problems that can be harmful to fish. Phosphate enters the aquarium from fish and invertebrate waste and decaying organic matter, such as dead algae and uneaten fish food. Excess phosphate contributes to unsightly algae and green water blooms. In saltwater, excess phosphate can inhibit the growth of hard corals. API PHOSPHATE TEST KIT for freshwater and saltwater aquariums contains two phosphate test bottles, test kit instructions, one capped test tube, and two color cards to accurately measure phosphate levels in fresh and saltwater aquariums. With API aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For almost 60 years API has developed premium solutions with proven and effective results for your family and ours. API offers a range of testing kits, water conditioners, and nutritionally superior food, because we’re dedicated to making a better underwater world. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. At API, we understand the rewards and relaxation of fishkeeping because we have a passion for fish too.