Although our 2-part formulas already provide sufficient levels of Calcium and Magnesium, some growers require supplementation helpful in demanding conditions. 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. Application Rates Add 2.5 mL per gallon of water during all stages as needed. See Feed Schedules for specific application recommendations. Best Practices Shake well before use. Use clean measuring instruments--do not put anything into the bottle. Some applications may require different dosages. Recommended for hydroponic use, especially with inert media and when using reverse osmosis (RO) water. Monitor EC regularly and adjust accordingly based on crop and growth stage. Adjust to pH to proper levels after mixing all fertilizers and additives. Store closed in original packaging at a temperature between 45° F and 85° F.