The presence of iron in water can manifest in several forms: colloidal iron, oxidized iron, soluble iron and iron bacteria. Colloidal iron is a special case of extremely small particles of oxidized iron that do not settle out. Oxidized iron is insoluble in non-acid water. Water containing oxidized iron is filled with some red rust when first drawn from the tap. Soluble iron is called “clear water iron” because the water is not red unless it stands.
Iron oxide deposits can plug up plumbing and other equipment that uses water, like farm equipment, home washing machines, hot water heaters and dishwashers. The other objection to iron in water is that it can cause reddish-brown stains on laundry, plumbing fixtures and cooking utensils. Iron causes a disagreeable metallic taste and, in some cases, can have a sewer type of odor. Iron causes coffee, tea, liquor and other beverages an inkier black. As little as 0.3 ppm is enough to cause iron staining.
Iron bacteria are living organisms that feed on iron in water and on iron in wells, piping, tanks and iron fixtures. The bacteria build slime in toilet water tanks and clog your pipes, pumps, water heaters and appliances. Until the last few years, iron bacteria were not too common a problem but their presence has increased rapidly throughout the country. These bacteria are now quite prevalent. You may expect that any iron water will at some future time, if not already, be invaded by iron bacteria. Iron bacteria must be killed by chlorination.
The presence and amount of iron in your water can be determined with testing. Iron is normally removed from water through mechanical filters, water softeners and reverse osmosis.