Liquid Reactor by Kent Marine 16 oz. Liquid Reactor is a complete calcium buffer system designed to give the same results as costly calcium reactor systems without investing in a reactor, CO2 tank, solenoid, and pH controller; also, there is no risk of overdosing CO2 and causing subsequent problems with algae and/or pH. This product will raise the concentrations of calcium, magnesium, strontium, and carbonates (alkalinity) in the system, and is chloride, phosphate, nitrate, and gluconate free! Each 16 oz. of Liquid Reactor will treat 5,000 gallons or 18,900 liters and contains 126,000 ppm of calcium and 193,000 ppm carbonates. Directions: Shake vigorously for 5-10 seconds immediately before each use! Add 5-10 ml (Cap on 16 oz. bottle equals 5 ml, Cap on 64 oz. and gallon equals 10 ml) per 55 gallons (200 L) aquarium capacity directly to an area of high water flow each day until target calcium level and alkalinity are reached. Active Ingredients: RO/DI water, chloride-free calcium, magnesium, and strontium salts from natural sources.