Hobby Ferrogan is a slowly soluble organic iron compound which simply and efficiently eliminates an iron deficiency of water plants. The iron (only in traces) is adsorbed by the water plants through an conversion of the compound. The strong chemical compound of the iron tho other components prevents a sudden over-fertilization so that Ferrogan is evenly releasing the required quantity of iron over a long period - just enough for each plant, group of plants or plant scene. Dosage: 15 g are sufficient for 1500 l water.