ME Coral Calcuim Powder MECoral uses only Pharmaceutical grade ingredients to achieve the highest quality, highest purity, and highest concentration possible. Quick guide: In order to increase Ca 10 ppm (400-410) in 100 gallons of aquarium water, add 100 ml or 3.4 fl oz of liquid solution. ME Calcium is ammonia, phosphate, and nitrate free. This makes the powder dissolve quickly and crystal clear with no residual impurities.