Limescale removal: safe ways to clear it, and what not to touch
White crust on taps and showerheads is harmless but annoying. A mild acid and some patience handle most of it.
Limescale is a hard, white or grey crust left when hard water dries. For taps, showerheads and kettles, a mild acid such as white vinegar or citric acid dissolves it. You do not need a harsh product for most jobs.
It is made of dissolved minerals, mainly calcium. If you keep seeing it, your water is probably hard. Our water hardness test shows how to check.
Taps and fittings
Soak a cloth in white vinegar and wrap it around the tap. Leave it for an hour, then wipe and rinse. A soft brush helps with the thread of the spout.
Test a small hidden spot first. Some tap finishes, such as brushed or coloured coatings, can be dulled by acid. If the maker gives care instructions, follow them.
Showerheads
Unscrew the head if it comes off by hand, then soak it in vinegar or a citric acid solution until the crust softens. Rinse well and clear the holes with a soft brush or a toothpick. If it does not unscrew easily, soak it in a bag tied around the arm instead of forcing it.
Kettles and glass
Fill a kettle with water and a little citric acid or vinegar, boil it, and leave it for a while. Rinse it out and boil clean water once or twice before you use it. Glass shower screens respond to a vinegar spray left for a few minutes, then wiped.
Things to avoid
- Never mix cleaners. Vinegar and bleach, or acid and many drain products, can release dangerous fumes.
- Keep acid off natural stone. Vinegar etches marble, limestone and some tiles.
- Do not scrape with metal. Scratches hold more scale next time.
Scale inside the hot water system
Scale also builds up inside hot water tanks and heating elements. It cuts efficiency and can make noises, but it is not something to clear with household acid. Do not open the system or touch its elements. A licensed plumber can flush and inspect it, and can tell you whether a softener makes sense in your area.
Is it worth fighting?
For appearance, a regular wipe is enough and cheaper than any gadget. Wiping a tap dry after use stops scale forming. A softener only earns its place if hard water is damaging appliances or heating elements, so find out how hard your water is before you buy one.
Which cleaner for which surface
A mild acid works on most limescale, but not on everything. Match the method to the surface before you start.
| Surface | What to use | Take care |
|---|---|---|
| Chrome or plain taps | White vinegar on a cloth wrapped around the tap for an hour | Test a hidden spot first |
| Brushed or coloured tap finishes | Follow the maker's care instructions | Acid can dull some finishes |
| Showerhead | Soak in vinegar or a citric acid solution | Clear the holes with a soft brush or a toothpick |
| Kettle | Boil water with a little citric acid or vinegar | Rinse and boil clean water before use |
| Glass shower screen | Vinegar spray left for a few minutes, then wiped | Do not scrape with metal |
| Marble, limestone and some tiles | Do not use vinegar | Acid etches natural stone |
| Inside the hot water system | Nothing. Call a licensed plumber | Do not open it or touch the elements |
Never mix cleaners. Vinegar and bleach, or acid and many drain products, can release dangerous fumes.
How to stop limescale coming back
Cleaning clears the crust. These habits and checks slow it down.
- Wipe taps and screens dry after use. Scale forms when hard water dries, so removing the water removes the cause.
- Find out how hard your water is. If you keep seeing scale, your water is probably hard. The water hardness test shows how to check.
- Repeat a mild soak before a crust gets thick. A second soak works better than a stronger chemical.
- Watch for signs inside the system. Scale in a hot water tank or element cuts efficiency and can cause noises. Ask a licensed plumber to flush and inspect it.
- Think hard before buying a softener. It only earns its place if hard water is damaging appliances or heating elements.
- Leave any plumbing change to a professional. Fitting a softener is licensed work.
Our water softener guide covers when one is worth it.
Frequently asked questions
What removes limescale fastest?
White vinegar or citric acid left on the scale for a while. Stubborn build-up may need a second soak rather than a stronger chemical.
Is limescale harmful to drink?
It is made of dissolved minerals and is generally not a health concern, but it can shorten the life of appliances.
Can I use vinegar on every tap?
Test a hidden spot first. Some finishes and natural stone can be damaged by acid.
Should I descale my hot water system myself?
No. Do not open it or touch the elements. A licensed plumber can flush and inspect it.
Sources
What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.
- NHMRC. Australian Drinking Water Guidelines
- Sydney Water. Water supply, wastewater and stormwater services