1. Liquid organic calcium source 2. Maintains calcium and accelerates coral growth 3. Concentrated (50,000 mg/L) FEATURE： Reef Calcium™ is a concentrated (50,000 mg/L) bioavailable polygluconate complexed calcium intended to maintain calcium in the reef aquarium without altering pH. Additionally, polygluconate contains no nitrogen or phosphorous, thus it is biologically impossible for it to lead to algae growth in a properly maintained reef system. DIRECTION： Add 1 capful (5 mL) per 80 L (20 US gallons) twice a week. You can increase the amount or frequency based on growth response but do not exceed 3 capfuls per 80 L (20 gallons) per day. Each capful will raise calcium by about 3 mg/L. Notes: Use the Reef Status™: Calcium test kit to measure calcium. It is not necessary to exceed 380 mg/L total calcium when using this product. Color and clarity may vary between lots. https://www.xinyangaquarium.com/