Hardness in water is quite easy to remove. A simple ion exchange water softener takes care of all but the most extreme levels of hardness content. One other thing that a softener does it remove or reduce certain types of iron as well. For low levels of specific types of iron, a water softener works quite well, but when the iron content is high or if the iron is not the right type, then a water softener will not do the job. In order to treat iron effectively, it is important to identify which type of iron your water might contain.
FERRIC IRON: This type of iron cannot effectively be removed with a conventional water softener. It will foul the softener’s resin media in a relatively short period of time. Ferric iron can be easily identified in water. The water will appear to have a reddish orange tint to it. This is oxidized iron and will stick to plumbing fixtures, pipes and stain laundry. Mechanical filtration such as a Birm filter or greensand filter are effective.
FERROUS IRON: This type of iron can be effectively removed with an ion exchange water softener so long as the concentration of ferrous iron is not over 3 parts-per-million (ppm or mg/L). This type of iron exists in water with a low oxygen content. If you were to fill a drinking glass with this type of water and leave it sit out all day, it would oxidize and the iron particles would accumulate on the bottom. Chlorination at the well, an ion exchange softener, a Terminator system, Sentry I Open Air System or a greensand filter will work on ferrous iron.
SEQUESTERED IRON: Often called Iron Bacteria, is able to pass through conventional softeners and other iron specific filtration systems. Because it can be broken down when heated, this type of iron is more noticeable in hot water. The best way to deal with iron bacteria is to prevent it from getting into the water system. Well chlorinators are very effective here such as the WellPro chlorinator or the Sentry I Open Air System.
HEME IRON: is most likely found in surface water. Standard iron removal equipment are usually ineffective at treating this type of water. Treating heme iron as tannins is standard practice. A water softener with a mixture of standard cation resin and anion resin is effective.