PRODUCT SUMMARY This is essentially a dry form of a cal mag boost with added benefits such as fish protein hydrolysate and a tiny amount of sulfur to give back what reverse osmosis takes out. Twenty percent calcium availability offers a lot of bang for your buck. Elemental is easily used as top dressing applications or as an amendment. If adding to a large quantity of water, first half fill a gallon jug with water, add the elemental and shake vigorously for a minute before adding to the tank. And always make sure to add Elemental before you add any other nutrients. NPK / 0.25 - 0 - 0.1 + CA 20% DERIVED FROM Calcitic Lime, Dolomitic Lime, Gypsum and Fish Protein Hydrolysate Roots Organics Elemental calcium and magnesium supplement was specifically created to augment calcium and magnesium levels and prevent deficiencies that can occur with fast-growing plants. Elemental contains two absolutely essential macronutrients: Calcium, an essential nutrient for plant health due to its role in cell walls, membranes and other biochemical processes; and magnesium, which is a central component of the chlorophyll molecule. Supplementing calcium and magnesium is one of the secrets of expert growers and results in more vigorous plants and larger yields.