Bulk Reef Supply Kalkwasser is one of the simplest and most cost-effective ways to maintain calcium and alkalinity levels in a reef aquarium. There are several methods to incorporate it into your system, and if your corals are thriving, adding kalkwasser can provide numerous benefits. As a unique solution that boosts both calcium and alkalinity, kalkwasser also helps increase your aquarium's pH while enhancing the purity of your auto top-off (ATO) water. Whether you choose to mix it directly into your ATO reservoir, use a kalk reactor, or set up a drip system, kalkwasser can be a game-changer for reef enthusiasts. The most popular approach is mixing it with your ATO water and letting your auto top-off system distribute small amounts of the saturated solution throughout the day, ensuring consistent delivery and optimal stability for your tank.