This is the Calcium portion of 2-part dosing.
- The carbonate-bearing component of a two-part method for dosing calcium and carbonates (the substances largely responsible for increasing alkalinity (”buffering capacity”) in the same ratio as that found in natural seawater.
- Ionically-balanced with respect to natural seawater concentrations of calcium and carbonates when used in equal amounts with Reef Cōde A.
- Benefits reef-building organisms such as corals, clams, calcareous algae, etc.
- Simplifies calcium and alkalinity maintenance.
- Stronger than most competing products.
- Contains no phosphate, silicate, or organic material.
- Formulated by a marine scientist.
More details found here: http://brightwellaquatics.com/products/reefcodebt.php