Mon to Fri 9:00 AM to 7:00 PM 333 Mountainview Rd S, Unit 11, Georgetown
905-702-2700
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Rotten-egg smell (sulphur)

A sulphur smell from the tap, often worst in hot water or first thing in the morning. Caused by hydrogen sulphide gas, and treatable at the point of entry.

Symptoms

  • Rotten-egg smell from the tap
  • Smell strongest in hot water or the shower
  • Smell first thing in the morning that fades with use
  • Black slime in toilet tanks or on fixtures
  • Tarnished silver or copper

Common causes

  • Hydrogen sulphide gas from sulphur bacteria in the well or aquifer
  • A reaction with the magnesium anode rod inside the water heater
  • Decaying organic matter in shallow or dug wells

How we treat it

  1. Find the source

    Hot only points to the water heater; hot and cold points to the well.

  2. Oxidizing sulphur filter

    Removes hydrogen sulphide at the point of entry.

  3. Catalytic carbon

    Polishes taste and odour after oxidation.

  4. Shock and heater service

    When the water heater is the cause.

The rotten-egg smell is hydrogen sulphide, a gas produced by sulphur bacteria in the well, in the aquifer, or inside the water heater. Because it is a gas, it escapes fastest from hot or agitated water, which is why the shower is usually where people notice it.

Where the smell comes from decides the fix. If it is only in hot water, the water heater anode or bacteria in the tank are the likely source. If it is in both hot and cold, the well is the source and an oxidizing sulphur filter with catalytic carbon at the point of entry treats the whole house. We test fresh at the tap because the gas dissipates quickly in a sample.

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