API Phosphate Test KitA fast, easy and accurate test kit used to test for phosphates, which can cause unsightly algae. Tests Phosphate levels from 0 to 10mg L or ppm. For fresh or saltwater use Phosphate can enter your aquarium through tap water, fish waste, and decaying organics such as uneaten food or dead algae. As phosphate increases so does your chance of having unsightly algae and green water blooms. High levels of phosphates are also harmful to plants. In salt