What is insoluble ferric iron?
Water containing ferrous iron is clear and colorless because the iron is completely dissolved. When exposed to air in the pressure tank or atmosphere, the water turns cloudy and a reddish brown substance begins to form. This sediment is the oxidized or ferric form of iron that will not dissolve in water. (1)
Resources
1. http://www.idph.state.il.us/envhealth/factsheets/ironFS.htm
