Seachem Kalkwasser is an exceptionally pure and soluble form of calcium hydroxide which is used to prepare Kalkwasser (limewater), that when added to marine aquariums helps to replicate the calcium content found in natural seawater. This beneficial formula helps to maintain calcium levels directly and carbonate alkalinity levels indirectly, but both are reliant upon the evaporation rate and CO2 concentration within the aquarium. Comes in a 500 g container.
Never add this product directly to the tank. Add 3 g (1 teaspoon) to 4 L (1 US gallon) of water and thoroughly mix until the solution has been dissolved. If you are using pure water, a fully saturated solution is prepared by adding 6 g (2 teaspoons) to 4 L (1 US gallon). Carefully drip this solution into tank. It is important to closely monitor the pH and carbonate alkalinity levels in the aquarium. Adjust the rate of addition to maintain a stable pH balance around 8.3-8.4.
Adding 4 L (1 US gallon) of a saturated kalkwasser solution to 150 L (40 US gallons) will raise the calcium content by 24 mg/L. Always use the clear supernatant (top solution) only and do not allow undissolved material (precipitates) to enter the aquarium. To avoid the formation and precipitation of calcium carbonate it is important to keep this container closed securely when not in use to minimize solution/air contact