Reef Calcium is a concentrated 50000 mgL 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. Reef Calcium utilizes a chained organic calcium rather than an ionic calcium. When a coral absorbs a molecule into its tissue it uses the same amount of energy regardless of molecular size. However charged molecules require more energy. When an uncharged molecule of Reef Calcium is absorbed the coral acquires multiple calcium atoms as well as an easily metabolized carbohydrate with less energy expended than it uses for ionic calcium uptake. Therefore at lower calcium levels corals can still take in as much calcium through our organic chains as they would at much higher levels of ionic calcium. Increases the bioavailability of the calcium Provides a rich source of metabolic energy Maintains peak coral growth Prevents calcium precipitationalkalinity depletion Will not lead to algae growth in a properly maintained reef system Directions 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 mgL.