Iron for for Organic Aquaponics Soluble - 10% - 16oz (196 gallons) (16oz) Highly Soluble and Suitable for all hydroponics, aquaponics, soil, and foliar applications Greenhouse grade - very pure and dissolves completely in water Prevents or corrects iron deficiencies - only 1/2 tsp per gallon needed Iron is recommended to be at 3-5mg/L or .04 - .07oz/100gallons in hydroponics or aquaponics Derived from Chelated Iron - 10% DTPA