API Phosphate Test KitAquarium Pharmaceuticals Phosphate Test Kit allows you to easily and accurately measure the phosphate level and maintain a healthy aquarium or pond. It does 150 tests. High phosphate leads to algae growth Helps maintain clear and healthy water For fresh and saltwater Why test your phosphate levels Well, phosphate can enter your aquarium through tap water, fish waste and decaying organics such as uneaten food or dead algae. As phosphate increases so