Fishy odours in water are relatively uncommon but may occur in both private wells and municipal water systems. The smell may resemble fish, seafood, marine odours or stale organic material and often becomes more noticeable when the water is heated.
The issue is commonly associated with organic compounds, biological activity or, in some cases, elevated levels of ammonium and nitrogen compounds. Surface water influenced by algae may also contain odour compounds perceived as fishy or earthy. The appropriate treatment method depends on the underlying cause.
Common Causes
- Organic Compounds in Water
- Algae and Surface Water Influence
- Biological Activity in Wells or Pipe Networks
- Ammonium and Nitrogen Compounds
- Water Heater or Internal Plumbing Issues
Common Symptoms
- Fishy or Seafood-Like Odour
- Odour Stronger in Hot Water
- Affected Taste
- Intermittent Odour Issues
- Often Without Visible Discolouration
Common Treatment Methods
- Water Analysis
- Activated Carbon
- Ozone
- Aeration and Degassing
- Cleaning of Wells or Tanks
- UV Disinfection as Final Barrier
Example Treatment Trains
Raw Water
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Activated Carbon
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UV Disinfection
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Drinking Water
Raw Water
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Ozone
↓
Activated Carbon
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UV Disinfection
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Drinking Water
Fishy odours may originate from several different causes, including organic compounds, algae, biological activity and internal plumbing issues. Water analysis and consultation with a qualified water treatment specialist are therefore generally recommended before selecting a treatment solution.