Orange or brown stains
This usually means iron, and water that is clear at the tap and rusty an hour later usually means the dissolved kind.
Dissolved iron is invisible until it meets air or chlorine, then it turns to rust particles and settles on whatever it is sitting on.
Look for stains that start where water drips or stands, laundry that comes out yellowed, and a filled glass that goes cloudy orange from the top down as it stands.
Do not buy an iron filter off a shelf. The right media depends on how much iron, in what form, and at what pH, and a stain alone does not give any of those.
Common questions
- What usually causes orange or brown stains on fixtures?
- Orange and brown staining usually means iron in the water. Water that is clear at the tap and turns rusty after standing usually means the dissolved form, which turns into rust particles once it meets air.
- Why does the water turn orange only after it sits in a glass?
- Dissolved iron is invisible until it reaches air or chlorine. It then oxidizes into fine rust particles, which is why a clear glass usually clouds orange from the top down as it stands.
- Can a water softener remove iron?
- Sometimes, within limits. It usually depends on how much iron there is, which form it is in, and the pH of the water. A softener sized without those three numbers is usually a guess, so the numbers usually come first.
Related: black stains and slimy orange or oily rainbow.