# Water Tank Cleaning in Kuala Lumpur | KL Plumbing Handbook

> How often to clean a water tank in a KL home, signs of a leaking or dirty tank, float valve basics, and KL1 Plumber

URL: https://klplumbing.my/water-tanks/
Last-Modified: 2026-11-15
Author: KL Plumbing Handbook editors

Quick answer

Clean a water tank whenever you see dirty or smelly tap water, sediment or algae, and check it once a year. An overflow pipe that drips means the float valve is not shutting off. A stain on the ceiling below the tank needs checking quickly. In condos, shared tanks are building management's responsibility.

![Sediment layer on the bottom of an open roof water tank seen in torchlight](/images/content/sediment-layer-on-the-bottom-of-an-open-roof-water.webp)

Sediment settles on the tank floor after repeated water cuts.

## What can go wrong with a water tank?

Most landed houses in the Klang Valley store water in a roof tank or a tank on a stand. Scheduled maintenance and burst mains cause water cuts, so a tank is useful storage. But tanks need attention. Our 

home plumbing guide for Kuala Lumpur

[/ →](/)

 covers what happens to tanks, pumps and heaters during a cut.

-   **Sediment** builds up with each refill, especially after an **Air Selangor water cut**.
-   **Algae** grows where light gets in through a poor lid or a translucent tank.
-   **The float valve** or **ball valve** sticks or wears, so the tank overflows or stops filling.
-   **Fittings leak** at the inlet, **tank outlet valve** or **overflow pipe**.
-   **Steel tanks corrode,** and plastic tanks crack with age and sun.

## What will you notice?

| Symptom | Likely cause | Guide |
| --- | --- | --- |
| Overflow pipe dripping | Float valve not shutting off | Water tank overflowing |
| Stain on the ceiling below the tank | Leaking tank or fitting | Roof leak or pipe leak? |
| Dirty, cloudy or smelly tap water | Sediment or algae | Brown or rusty tap water |
| Tank not filling | Float valve stuck, blocked inlet, low supply | See below |
| Rust or cracks | Ageing tank | Repair or replace? |

## How often should a tank be cleaned?

Clean it when you see the signs: sediment on the bottom, slime on the walls, dirty or smelly water at tank-fed taps. Put a tank check on your 

yearly home plumbing checklist

[/guide/yearly-home-plumbing-checklist/ →](/guide/yearly-home-plumbing-checklist/)

, and look again after long or repeated water cuts.

## What can you safely check yourself?

Only if you can reach the tank safely, with boards to stand on in the **roof space**, good light and a cool time of day:

1.  Look at the water for sediment, algae or anything floating.
2.  Check the lid fits.
3.  Look for rust, cracks and damp around the fittings and below the tank.
4.  Lift the float arm gently. Does the water stop?
5.  Check the overflow pipe outside is dry.

Never stand on ceiling boards.

## Tanks and water cuts

A full tank can carry a household through a short water cut. Before a planned cut, check the tank is full. During it, switch off the booster pump if the tank may run dry. After it, expect some sediment. Our guide to a 

water cut in the Klang Valley

[/guide/water-cut-what-to-do-klang-valley/ →](/guide/water-cut-what-to-do-klang-valley/)

 covers each step.

## Choosing a tank

Stainless steel and polyethylene tanks both work well when well made and well installed. Our comparison of 

stainless steel and polyethylene water tanks

[/guide/stainless-steel-vs-polyethylene-water-tank/ →](/guide/stainless-steel-vs-polyethylene-water-tank/)

 covers durability, weight, algae and sizing.

### Condo unit

Shared tanks belong to the building. If tap water is dirty across several units, ask building management when the tanks were last cleaned.

## When should you call a plumber?

Call a plumber if the overflow keeps running, the tank leaks, the water stays dirty after cleaning, you see corrosion or cracks, or you cannot reach the tank safely. The partner’s published tank cleaning and replacement prices, with source and date, are listed further down this page.

## Partner published prices

KL1 Plumber's published starting prices, read from kl1plumber.com/price on 15 November 2026

| Job | KL1 Plumber published price (read 15 Nov 2026) |
| --- | --- |
| Clean water tank | RM200 to RM300 |
| Replace water tank | RM500 to RM1,000 |

Source: 

kl1plumber.com/price

[https://kl1plumber.com/price/ →](https://kl1plumber.com/price/)

, read 15 November 2026. These are the partner's own prices, not market averages. Prices can change, so check the source before you rely on them.

## Signs of water tanks at home

Everyday signs, photographed in Klang Valley homes

![Overflow pipe dripping from the eaves of a terrace house onto the side lane](/images/misc/overflow-pipe-dripping-from-the-eaves-of-a-terrace.webp)

A dripping overflow pipe means the float valve is not closing.

![Water stain on a ceiling board directly below where the roof tank sits](/images/misc/water-stain-on-a-ceiling-board-directly-below-wher.webp)

A stain below the tank can mean a leaking tank or fitting.

![Glass of slightly cloudy tap water held up to the light in a Malaysian kitchen](/images/misc/glass-of-slightly-cloudy-tap-water-held-up-to-the-.webp)

Cloudy or smelly tap water can come from a dirty tank.

![Blue polyethylene water tank on an outdoor steel stand beside a landed house](/images/misc/blue-polyethylene-water-tank-on-an-outdoor-steel-s.webp)

Tanks on stands are easier to reach but need checking for rust.

## Water Tanks guides

Every guide in the Water Tanks section

Guide Water Tank Overflowing Why a roof tank overflows or drips from the overflow pipe: stuck float or ball valve, worn washer, and the risk to your ceiling. Read guide arrow\_forward

[/guide/water-tank-overflowing/ →](/guide/water-tank-overflowing/)

 

Decision guide Stainless Steel vs Polyethylene Water Tank Compare stainless steel and polyethylene tanks for KL homes: durability, weight on the roof, algae and heat, and sizing. Read guide arrow\_forward

[/guide/stainless-steel-vs-polyethylene-water-tank/ →](/guide/stainless-steel-vs-polyethylene-water-tank/)

 

Decision guide Water Tank Repair or Replacement? When a leaking or ageing tank can be repaired and when it should be replaced, with KL1 Plumber's published replacement price (Nov 2026). Read guide arrow\_forward

[/guide/repair-or-replace-water-tank/ →](/guide/repair-or-replace-water-tank/)

## Questions people ask

Do I need a water tank?expand\_more

Many landed houses in the Klang Valley have one, because it stores water through water cuts and feeds taps by gravity. In condos, the building has shared tanks managed by building management.

What is a float valve?expand\_more

It is the valve that lets water into the tank. A float rises with the water and shuts the valve when the tank is full. If it sticks or wears, the tank overflows or stops filling.

Can I clean the tank myself?expand\_more

Some owners do, but it means draining the tank, working in a hot roof space and handling cleaning products safely. Many prefer a plumber, especially if access is difficult.

How often should a water tank be cleaned?expand\_more

Clean it whenever you see signs such as dirty or smelly tap water, sediment, or algae, and include a tank check in your yearly plumbing checklist. KL1 Plumber's published tank cleaning price is RM200 to RM300 (read 15 November 2026).

About the authors

KL Plumbing Handbook editors

The KL Plumbing Handbook editors write plain-language guides on home plumbing problems, repair costs and hiring a plumber for homes in Kuala Lumpur and the Klang Valley. Each guide covers one problem and states the source and date of every cost figure.

Spotted an error? 

Send a correction

[/contact/ →](/contact/)

. See our 

editorial policy

[/editorial-policy/ →](/editorial-policy/)

.

## Related sections

Water Pumps Booster pump types, noisy or failing pumps, and installation basics. Go arrow\_forward

[/water-pumps/ →](/water-pumps/)

 

Water Pressure Causes of weak pressure in landed houses and high-rise units, and when a booster pump makes sense. Go arrow\_forward

[/water-pressure/ →](/water-pressure/)

 

Roof Leaks and Waterproofing Ceiling stains, roof leaks, bathroom and balcony waterproofing. Go arrow\_forward

[/roof-leaks-and-waterproofing/ →](/roof-leaks-and-waterproofing/)