Purple-Up™ uses a unique dual method approach to coralline algae acceleration. It contains ionic calcium which immediately raises dissolved calcium levels in your aquarium water. At the same time Super Sea Calcium™ (a 10 micron Aragonite powder derived from natural seawater) targets the live rock surface. Super Sea Calcium™ dissolves in situ; delivering calcium, strontium, magnesium, and carbonate right where it’s needed. Aslo available in 16oz.