1) Soluble

"Clear water" iron, is the most common form and the one that creates the most complaints by water users. This type of iron is identified after you've poured a glass,of cold clear water. If allowed to stand for a few minutes, reddish brown particles will appear in the glass and eventually settle to the bottom.

2) Insoluble

When insoluble iron, or "red water" iron is poured into a glass, it appears rusty or has a red or yellow color. Insoluble iron can create serious taste and appearance problems for the water user.

Because iron combines with different naturally occurring acids, it may also exist as an organic complex. A combination of acid and iron, or organic iron, can be found in shallow wells and surface water. Although this kind of iron can be colorless, it is usually yellow or brown.

Finally, when iron exists along with certain kinds of bacteria, problems can become even worse. Iron bacteria consume iron to survive and leave a reddish brown or yellow slime that can clog plumbing and cause an offensive odor. You may notice this slime or sludge in your toilet tank when you remove the lid.

Treatment considerations for various forms of Iron (Click on one of the options for more information.)

• Filtration: Media used to entrap and screen out oxidized particles of iron. Usually requires backwashing to remove accumulated iron.

• Water Softener: Removal of soluble iron by ion exchange.
• Manganese Greensand: An ion exchange sand material which is capable of removing iron. Adsorbs dissolved iron and requires chemical regeneration.
• Catalytic Filtration "BIRM": A granular filter medium that enhances the reaction between oxygen and iron and then filters the insoluble iron.
• Ozonation: A specialized form of aeration using ozone to convert soluble iron.
• Ion Exchange: Substituting an acceptable ion (such as sodium) for soluble iron.
• Chlorination: Chemical oxidizer used to convert soluble iron to an insoluble, filterable form.

-Information collect from Department of Natural Resources can be found at :

-http://www.dnr.state.wi.us/org/water/dwg/iron.htm-