Athena CaMg is designed to supplement either of our 2-part liquid formulas. Some cultivars and growing conditions may require higher doses of Calcium, Magnesium, Iron and Nitrogen during heavy growth and development phases. This product effectively corrects these common deficiencies without throwing off overall elemental balance. In systems using reverse osmosis (RO) water and plants grown in inert media, such as coco and rockwool, Athena CaMg is particularly useful. Although our 2-part formulas already provide sufficient levels of Calcium and Magnesium, some growers require find supplementation helpful in demanding conditions. Application Rates Add 2.5 mL per gallon of water during all stages as needed.