Does Your Water Tank Smell Like Dead Fish? Here’s How to Get Crystal-Clear, Safe Water This Monsoon

Experts warn that neglected overhead water tanks can become breeding grounds for bacteria, algae and insects during the rainy season. Simple cleaning habits can help prevent foul-smelling water and protect your family’s health.

By Vidhi Lalla 

Pune: With the arrival of the monsoon, many households focus on cleaning their homes but often overlook one of the most important sources of daily hygiene—the drinking water tank. If your tap water has started smelling like fish or has an unpleasant odour, the problem could be coming from the storage tank rather than the water supply itself.

Experts say stagnant water, algae, dirt, bacteria and decaying organic matter can accumulate inside overhead tanks, especially during the rainy season. Dust, leaves, insects and mosquitoes can also enter if the tank lid is not tightly sealed, leading to contamination and foul-smelling water. Such contamination can increase the risk of stomach infections, diarrhoea and other water-borne illnesses.

To maintain safe drinking water, experts recommend thoroughly cleaning household water tanks at least once every three months. Ideally, the tank should be emptied before cleaning so that algae, sludge and dirt can be scrubbed off the walls and floor using a soft brush. The tank should then be rinsed thoroughly with clean water before refilling.

If the water develops only a mild odour, natural remedies such as lemon juice may help reduce the smell temporarily. However, experts caution that these methods should not replace proper cleaning if the tank is heavily contaminated.

Where bacterial contamination is suspected, chlorine may be used in the recommended quantity to disinfect the tank. However, the water should be allowed to stand for the prescribed contact time and, where necessary, filtered before being used for drinking.

For households facing water shortages, cleaning the tank without completely draining it is possible, though it is less effective than a full clean. Long-handled non-abrasive brushes, wet or dry vacuum cleaners, or sludge pumps can be used to remove sediment while conserving water. Mild food-safe cleaning agents such as diluted white vinegar or baking soda paste may be used only on the walls above the waterline, ensuring they do not contaminate the stored water.

Experts also advise turning off the inlet water supply before cleaning, wearing waterproof gloves, using a stable ladder while accessing rooftop tanks and avoiding harsh chemicals that could contaminate drinking water.

Choosing a high-quality water tank with UV-resistant material, keeping the lid tightly closed and ensuring regular water circulation can also help prevent algae growth and foul odours. Regular inspection of the tank, especially during the monsoon, can go a long way in ensuring safe and clean drinking water for the entire family.

FAQs

1. Why does my water tank smell like fish?
A fishy smell is usually caused by algae, bacteria, decaying organic matter or stagnant water inside the tank. Contamination is more common during the monsoon if the tank is not cleaned regularly.

2. How often should a household water tank be cleaned?
Experts recommend cleaning drinking water tanks at least once every three months. Tanks may require more frequent cleaning during the rainy season or if contamination is visible.

3. Can I clean my water tank without emptying it?
Yes. Sediment can be removed using a sludge pump or wet vacuum, while the walls above the waterline can be cleaned with long-handled brushes. However, a full drain-and-clean remains the most effective method.

4. Is lemon juice enough to remove bad odours from tank water?
Lemon juice may help reduce mild odours, but it cannot eliminate heavy contamination caused by bacteria, algae or sludge. Proper cleaning is necessary if the tank is dirty.

5. What are the best ways to keep a water tank clean?
Keep the lid tightly closed, clean the tank every three months, prevent stagnant water, inspect for algae and insects regularly, and use only food-safe cleaning methods or approved disinfectants when required.

Disclaimer: If the water has a strong odour, unusual colour or visible contamination, avoid consuming it until the tank has been thoroughly cleaned and the water quality is restored.