The Reef Code A Balanced Calcium & Alkalinity System from Brightwell Aquatics is the calcium-bearing component of a two-part method designed to dose calcium and carbonates in marine aquariums, mimicking natural seawater concentrations. This product is ionically balanced with respect to natural seawater when used in equal amounts with Reef Cōde B, providing optimal conditions for reef-building organisms such as corals and clams. It simplifies the maintenance of essential water parameters by ensuring a stable and adequate supply of calcium and alkalinity without introducing unwanted substances like phosphate or silicate.