AragaMilk provides a simple way to add balanced calcium, carbonate buffer, and essential trace elements like strontium, magnesium, and barium to your marine or hard-water aquarium. AragaMilk uses the power of natural aragonite for flash mineralization, plus a boost of magnesium to aid in coralline algae growth. No parts to mix, no risk of overdose. Dosing varies. Approximately 1 drop per 2-4 gallons. 16 oz. container.