Iron and Rust: Problems and Solutions


Iron is one of the most common elements on earth and can be found in almost all natural water supply sources. Learn more about its impact on our drinking water below.

While trace levels of iron are harmless, high iron levels can make water taste metallic, and turn it red, brown, or yellow in color. High iron can also deposit brown, orange or yellow stains on kitchen and bath fixtures, as well as washing machines and clothing.

How the levels of iron can affect water treatment

The most common iron in water supplies is ferrous, or "clear-water", soluble iron. If your water comes out of the faucet clear, but has red or yellow colorization after standing, you probably have ferrous iron in your water.

If you can see red-brown particles settling at the bottom of your drinking glass, it’s ferrous iron.

Less common is ferric iron, or “red water" iron, which makes water rusty or yellowish in color, and is distinctly unpleasant to drink.

Iron water treatment recommendations

In order to deal with iron in your water, you need to establish the type and severity of the problem. 

Ferric Iron treatment

Because ferric iron is in particulate form, it can be treated with sediment filtration.

If there are rust or iron particles from plumbing corrosion, sediment filtration will treat the issue.

Sediment filter cartridge system

However, if you have both ferric and ferrous iron in your water, you will need to treat the ferrous iron with specialty iron reduction filtration.

The EPA recommends that safe water includes less than 0.3 parts per million (ppm) of iron. If your water has iron above this level, recommended treatment depends up on the iron level.

For water with up to 3 ppm of iron, you can use an Iron Cartridge Whole House System.

Iron and Manganese Cartridge System

If you have both hard water, and up to 4 ppm of iron, you can use the Whole House Hardness, Iron and Manganese and Water Softening System by Tier1.

Hardness, Iron and Manganese Reduction Softening System

For water over 4 ppm, you can use the Whole House Iron, Manganese and Hydrogen Sulfide Air Induction Oxidization Filter System by Tier1.

Iron, Manganese and Hydrogen Sulfide AIO System

Another solution for iron removal is KDF filtration.

KDF Filtration

Kinetic Degradation Fluxion (KDF) is a high-purity copper-zinc formulation. KDF uses a chemical process known as redox (oxidation/reduction). This chemical process removes iron, chlorine, mercury, lead, and hydrogen sulfide from water supplies.

The KDF redox process works by exchanging electrons with contaminants, changing them into harmless components. During their reactions, electrons are transferred between molecules and new elements are created.

KDF 55 and KDF 85

The two types of KDF most often used for water filtration are KDF 55 and KDF 85.

KDF-55 Media: reduces chlorine and soluble heavy metals. A KDF-55 filter media can remove over 99% of free chlorine. For chlorine removal in point-of-use applications, KDF media is incorporated into shower filters and into cartridge at the tap. Listed as a microbial device by the EPA for its outstanding bacteria control, KDF is bacteriostatic.

KDF-85 Media: reduces iron and hydrogen sulfide. KDF 85 is efficient at removing iron and hydrogen sulfide. KDF-85 also controls scale, bacteria and algae. Like KDF55 media, KDF85 uses the redox method to remove chlorine, chlorinated hydrocarbons, hydrogen sulfide, iron, and metals like lead, arsenic, aluminum, mercury, and cadmium from water. KDF process media act as catalysts to change soluble ferrous cations into insoluble ferric hydroxide, which is easily removed by regular backwashing. KDF 85 medium removes more than 90% of iron from groundwater supplies.

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