Iron Removal will keep your drinking and bathing water clean and healthy, and can prevent those unsightly red-orange stains.

I have red stains in my sinks and other fixtures!

Iron can cause red-orange stains to appear. You must test the water to determine the amount and type of iron you have (oxidized, soluble, colloidal, bacteria, or organic-bound, see below). Iron can stain clothing and dishes too, so it is definitely a problem that should be fixed!

Oxidized:

This type of iron is usually found in a surface water supply. This is water that contains red particles when first drawn from the tap. The easiest way to remove this type of iron is by a fine mechanical filter. A cartridge-type filter is usually not a good solution due to the rapid plugging of the element. Another method of removal is by feeding a chemical into the water to cause the little particles of iron to clump together. It will then fall to the bottom of a holding tank where it can be flushed away.

Soluble:

Soluble iron is called "clear water" iron. After being drawn form the well and contacting the air, the iron oxidizes (rusts), forming reddish brown particles in the water. Depending on the amount of iron in the water, you can solve this problem with a water conditioner, or a combination of softener and filter. You can use an iron filter that recharges with chlorine or potassium permanganate. You can also feed chemicals to oxidize the iron, then filter it with a mechanical filter. You can sometimes hide the effects of soluble iron by adding chemicals that, in effect, coat the iron in the water and prevent it from reaching oxygen and oxidizing.

Colloidal:

Colloidal iron is very small particles of oxidized iron suspended in the water. They are usually bound together with other substances. They resist clustering together due to the static electrical charge they carry. Because these particles are so small, this iron looks more like a color, rather than particles, when looked at in a clear glass. There are two popular treatments: feed chlorine to oxidize the organic away from the iron. This will allow clustering to occur. Another way is to feed polymers that attract the static charge on the particles, forming larger clumps of matter that is filterable.

Bacterial:

Iron bacteria are living organisms that feed on the iron found in the water, pipes, fittings, etc. They build slime along the water flow path. Occasionally, the slimy growths break free, causing extremely discolored water. If a large slug breaks loose, it can pass through to the point of use, plugging fixtures. These types of bacteria are becoming more common throughout the United States. If you suspect bacteria iron, look for a reddish or green slime buildup in your toilet flush tank. To confirm your suspicions, gather a sample of this slime and take it to your local health department/water department for observation under a microscope. This type of iron problem is very hard to eliminate. You must kill the bacteria, usually by chlorination. You must use high amounts of chlorine throughout your plumbing system to kill all organisms. It may be necessary to feed chlorine continuously to prevent regrowth. A filter alone will not solve this problem.

Organic Bound:

When iron combines with tannins and other organics, complexes are formed that cannot be removed by ion exchange or oxidizing filters. This iron may be mistaken for colloidal iron. Test for tannins. If they are present, it is most likely combined with the iron. Low-level amounts can be removed by using a carbon filter. This absorbs the complex. You must replace the carbon bed when it becomes saturated. Higher amounts require feeding chlorine. This will oxidize the organics to break apart from the iron and cause both to precipitate into a filterable particle.

How does the Iron Removal process work?

Most iron removal water filtration systems work with the notion that the iron needs to be oxidized to convert it from a ferrous (dissolved) state to a ferric (undissolved) state. , The iron can then be filtered out properly.

What is pH and what role does it play?

The pH (potential of Hydrogen) of a water source plays a very important role in understanding the way that the iron can convert from a ferrous (dissolved) state to a ferric (undissolved) state. The higher the pH level, the faster iron can convert. It is suggested to have a pH of at least 6.5 or higher for the iron to convert.

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