Athena Pro Core provides strong baseline nutrition across all stages of plant growth. Nitrogen to assemble chlorophyll and amino acids. Calcium to build structure. Essential microelements to catalyze photosynthesis, enzyme production and a multitude of important plant processes. Readily available Nitrogen, Calcium, and essential microelements Fully soluble dry fertilizer, no particulates or sediment Works with any dosing system: Dosatron, Netaflex, Rhythm Mixes completely at room temperature Low heavy metal content Ideal for mixing stock tanks and compatible with all dosing systems. This large-grind mix is 100% soluble and will not clog irrigation systems or leave sediment in reservoirs. We discourage mixing Pro Line in small amounts directly into the reservoir. We would rather turn the Pro line into a concentrated liquid first and then use that liquid to mix your batch tanks. Nutrient Preparation Steps for a STOCK CONCENTRATE: Get a measuring container that has accurate gallon marks on it. Fill half of the stock tank with water. Slowly pour granules into water while agitating, then mix thoroughly to solubilize. Add additional water until it gets exactly to the 12.5 gallon mark. Vigorously mix until all granules are solubilized. 5 - 5 lb bags