Rotten-egg smell
Why does my well water smell like rotten eggs?
Hydrogen sulfide gas, usually worse on the hot side, comes from sulfate-reducing bacteria or sulfur in the formation.
How you notice it
- Rotten-egg smell, strongest on hot water
- Tarnished silverware and brass
- Smell returns days after bleaching the well
Why it happens
Sulfate-reducing bacteria in the well or the water heater convert sulfate to hydrogen sulfide gas. Deep bedrock wells are the usual setting.
The fix
- Air-injection oxidation sized for sulfide, not just iron
- Replace a magnesium water heater anode with aluminium if the smell is hot-side only
- Shock-chlorinate the well and lines before judging results
Equipment that solves it
Recommendations are generated from Canadian regional well records. Links are affiliate links — we may earn a commission at no extra cost to you.
SpringWell WS1 Air-Injection Iron & Manganese Filter
Oxidizes dissolved iron and manganese, then filters it out — no chemical feed, no staining.
$60/yr consumables · standard
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US Water Systems Matrixx Infusion Iron & Sulfur System
For carbonate and sandstone wells with heavy iron plus rotten-egg sulfur odour on the hot side.
$90/yr consumables · premium
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iSpring WGB22BM 2-Stage Iron & Manganese Whole-House Filter
Entry option for light staining. Expect cartridge changes every 2–3 months.
$140/yr consumables · budget
Shop this stageWhere this is common in Canada
Regions whose modelled groundwater matches this problem.
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