Precision Integrate Part A is a well-balanced supplement that is designed to raise and maintain calcium levels as well as enhance coral growth. This product contains 75,000 ppm (mg/L) of calcium and is one of the most concentrated two part products on the market today. Nearly every inhabitant of a marine reef aquarium uses calcium, including calcareous (coralline) algae, snails, crustaceans, corals and other invertebrates. Precision Integrate Part A does not contain polygluconates, lactates, phosphates or nitrates, which can cause unwanted algae, slime and bacterial growth. Precision Integrate Part A is made with high quality (USP Grade) chemicals, which ensures you will not be adding unwanted amounts of metals or organics to your aquarium.