The Reef Fusion Two Part System by SeaChem is designed to maintain the critical levels of calcium and alkalinity essential for healthy coral growth in reef aquariums. This system includes Reef Fusion 1, which provides calcium along with magnesium, strontium, boron, iron, manganese, and molybdenum at biologically appropriate levels. Reef Fusion 2 contains a mixture of carbonates and bicarbonates to restore and maintain alkalinity in the water, providing essential carbonate for calcareous species growth. When used as directed, this system ensures that your reef aquarium has the necessary elements for vibrant coral health and development.