The Seachem Reef Kalkwasser Saltwater Conditioner for Aquariums is a pure calcium hydroxide with unparalleled purity and solubility. Calcium hydroxide is used to make limewater (kalkwasser) solutions that keep calcium concentrations in seawater at natural levels. Calcium is maintained directly in kalkwasser solutions, and carbonate alkalinity is maintained indirectly. However, its ability to perform these functions is affected by the rate of evaporation and the concentration of CO2. If these two elements are insufficient, you can supplement calcium with Reef Advantage Calcium, Reef Complete, or Reef Calcium, and carbonate alkalinity with Reef Builder or Reef Carbonate (do not mix these directly with a kalkwasser solution).
