Well-water iron and sulfur: what to do about the smell
Rotten-egg smell, orange staining in toilets, metallic taste, and the train of equipment that fixes them.
December 4, 2025
Well-water iron and sulfur are the most common reasons we get a service call from outside city limits. Both are smell-and-taste problems on the surface, and both are equipment-failure problems underneath.
Iron: orange and staining
Dissolved ferrous iron is clear in the well, then oxidizes to ferric iron the moment it hits air. That is what stains your toilets orange. Anything over 0.3 ppm shows up visually.
Sulfur: the rotten-egg smell
Hydrogen sulfide gas dissolved in the water. Smelled at concentrations under 0.1 ppm. Triggered by sulfate-reducing bacteria in the well.
The treatment train
- Air-injection oxidizer, converts ferrous iron to ferric and oxidizes sulfide to sulfur
- Backwashing media filter, captures the oxidized iron and sulfur
- Softener, protects appliances from the remaining hardness
- UV at the end, handles any biology the media filter does not
This is what every Sanctuary tier install includes. It is not a single piece of equipment. It is a sequence.
