Iron, manganese and hydrogen sulfide are the most common complaints from well owners. They are mostly nuisance problems rather than health risks, but they stain fixtures and laundry, clog plumbing and make water unpleasant enough that people stop drinking it.
Which iron problem do you have?
- Clear water that turns orange after it sits: dissolved (ferrous) iron, which oxidizes in air. The most common kind.
- Water that comes out orange or cloudy: iron that has already oxidized (ferric), often with sediment.
- Slimy orange or brown film in the toilet tank: iron bacteria. Not a health risk, but they foul treatment equipment, so shock chlorinate before installing a filter.
- Black or dark brown stains: manganese, often alongside iron. Manganese also has an EPA health advisory level of 0.3 mg/L, so get a number from a lab.
EPA's secondary guideline for iron is 0.3 mg/L; staining usually starts around there.
Rotten-egg smell: hot water only, or everything?
- Only the hot water smells: the water heater is the likely source. Sulfate in the water reacts with the heater's magnesium anode rod. Replacing it with an aluminum-zinc or powered anode usually ends the smell.
- Hot and cold both smell: hydrogen sulfide is in the groundwater, sometimes from sulfate-reducing bacteria in the well. Shock chlorination helps if bacteria are the cause; gas from the aquifer itself needs treatment.
What removes it
- Air-injection oxidizing (AIO) filters. A pocket of air in the tank oxidizes iron, manganese and hydrogen sulfide, and the media traps the particles. Backwashes itself, no chemicals. The usual choice for moderate levels.
- Chemical oxidation (chlorine or hydrogen peroxide injection, then a filter) for high levels or when iron bacteria are present.
- Water softeners handle small amounts of dissolved iron alongside hardness, but high iron fouls the resin.
- Catalytic carbon works for low levels of hydrogen sulfide.
- Sediment cartridges catch already-oxidized iron but clog quickly; they are a pre-filter, not a fix.
Test first
Order a lab panel that includes iron, manganese, hydrogen sulfide or sulfate, pH and hardness. Each of those numbers changes which equipment works, and low pH limits some iron filters. See how to build a well system once you have results.