Pet Product News Editor's Choice Awards Winner as One of the Best New Products of 2005! Has a unique dual method approach to coralline algae acceleration: 1. Ionic calcium?Immediately raises dissolved calcium levels in your aquarium water. 2. Ten micron aragonite?targets the live rock surface, where it dissolves in situ (in place), delivering calcium, strontium, magnesium and carbonate right where it is needed. Features: * Iodine Replenishment: PurpleUp replenishes iodine, an essential element for coralline algae tissues that quickly becomes depleted in closed systems. * Easy to use. One bottle of Purple Up replaces the typical multi-product recipe for successful coralline algae growth favored by advanced aquarists. * Contains Super Sea Calcium, a natural calcium derived from pristine tropical oceans. * Treats up to 4730 gallons.