RAW Calcium/Mag (9-0-0) contains 15% calcium and 3% magnesium. RAW Calcium/Mag has optimized the ratio of each element in a water soluble formulation of calcium nitrate and magnesium sulfate so that it doesn’t leave the media salty. This product is a stand alone Calcium / Mag supplement. Due to its low dilution rates a little RAW Calcium / Mag goes a long ways. One packet makes up to 200 gallons! Its also ideal for preventing deficiencies, treating deficiencies and for creating optimal recipe solutions.