Iron
Fe·Affects skin,
The most common well-water nuisance. Iron dissolves out of soil and rock into groundwater, then oxidizes on contact with air to leave orange and brown stains on fixtures, laundry, and skin.
Fe
EPA limit
No federal MCL (secondary standard 0.3 mg/L for cosmetic effects)
Most at risk
Well-water households, anyone with iron-rich soils or rust-prone plumbing
Found in
Well water
AquaOx filters
YesIron-specific media (AquaOx FE Edition)
What it does to you
Health effects
Iron in drinking water is not classified as a health hazard at the concentrations typical of well water. Iron is an essential nutrient, and the body regulates uptake from drinking water in the same way it regulates dietary iron.
The EPA does not set an enforceable Maximum Contaminant Level (MCL) for iron. The 0.3 mg/L secondary standard is a cosmetic recommendation, not a health limit. At concentrations above this, iron causes orange or brown staining on fixtures, laundry, and dishware, gives water a metallic taste, and produces visible sediment.
Rare exceptions: people with hereditary hemochromatosis (an iron-overload disorder) should not drink iron-rich water because their bodies cannot regulate absorption normally. Iron-loving bacteria can also harbor pathogens, so heavy iron-bacteria slime in plumbing is a secondary water-quality concern beyond just staining.
Where it comes from
How it gets into your water
Iron dissolves out of iron-bearing minerals in soil and bedrock. As groundwater moves through these formations, the iron leaches into solution. Most well water in the Midwest, Northeast, and parts of the Southeast has measurable iron because the underlying geology is iron-rich.
Two chemical forms matter. Ferrous iron (Fe2+) is dissolved and invisible in water straight from the well: the water looks clear in a glass but turns orange after sitting in air for a few minutes as the iron oxidizes. Ferric iron (Fe3+) is already oxidized and shows up as orange or brown particles in the water immediately.
Iron can also enter water from corroding iron and steel plumbing, particularly in older homes with galvanized pipes that have started to fail. This is a smaller contribution than geological iron in most cases.
Iron-rich geology
Bedrock dissolution into groundwater
Corroding iron pipes
Old galvanized plumbing
Iron-reducing bacteria
Biofilm in well casings
Water heater corrosion
Tank sediment from aging units
Find out for yourself
Is it in your water?
Iron is the easiest contaminant to identify visually. Orange staining in toilet bowls, around faucet aerators, and on white laundry is a near-certain indicator. A metallic taste in tap water is another giveaway. A standard well-water test from a county extension office or certified lab will give you a precise concentration.
If your water comes out clear but turns orange in a glass within minutes, you have ferrous (dissolved) iron. If it comes out already colored or has visible orange particles, you have ferric (oxidized) iron. Both are treatable, but the right media depends on the form and concentration.
The fix
How AquaOx filters it
The AquaOx FE Edition is the iron-specific configuration in our lineup. It uses an oxidizing iron-filtration media that converts dissolved ferrous iron to its ferric form and filters it out in a single pass. The FE Edition is sized to handle high iron loads (above 3 mg/L) and includes the regeneration capacity to keep the media performing over years.
The standard AquaOx whole-house system handles low iron levels (under 1 to 2 mg/L) along with everything else it filters. For homes with severe orange staining, persistent metallic taste, or measured iron above 3 mg/L, step up to the FE Edition.
One important caveat: iron bacteria require separate treatment. If your well has a slimy reddish-brown biofilm on the inside of the toilet tank or pump components, you have an iron-bacteria infestation that calls for shock chlorination before any filter will keep up with the load.
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