The car is freshly washed – and after drying it's covered in white dots and rings. The culprit is usually not the shampoo but the water. In many regions of Switzerland, tap water is hard, meaning it contains a lot of limescale. You can find out how hard your water is from your water supplier or on your municipality's website.
How limescale spots form
When a drop of water evaporates on the paint, the dissolved minerals stay behind. The harder the water and the warmer the paint, the faster and more visible the spots. They are especially noticeable on dark paint and on glass.
How to avoid limescale spots
- Never wash in the sun. Cool paint means slower evaporation.
- Work section by section and don't let the car dry on its own.
- Dry immediately. A large microfibre drying towel such as the 7WASH Drying Towel 60 × 90 cm absorbs the water before it evaporates. Lay it on and pull instead of rubbing.
- Use softened water for the final rinse. With a mobile water softener such as the Aquain V1, you rinse with limescale-free water. The system connects to your garden hose and also works with pressure washers.
- Seal the paint. Water beads off a sealed surface more easily, so fewer drops are left behind – for example with 7WASH Hydro Slick.
Removing fresh limescale spots
- Light, fresh spots can often be removed with 7WASH Wash & Wax Waterless and a clean microfibre cloth.
- On glass, 7WASH Glass Cleaner helps.
- Etched-in spots that remain after several attempts are a job for a professional detailer – don't treat them with abrasives.
Who benefits from a water softener?
If you often wash your car yourself, drive a dark-coloured car or use a pressure washer and foam sprayer, you'll benefit the most. For garages and detailers there are larger systems such as the Aquain System V3. You'll find all models in the Aquain collection.
Frequently asked questions
How do I know how hard my water is?
Your water supplier or municipality publishes the water hardness, usually in French degrees of hardness (°fH).
Do household limescale removers help?
Household descalers are not designed for car paint. Use car care products and, if in doubt, a professional.
Do I need softened water for the whole wash?
It makes the biggest difference for the final rinse, because that water is what stays on the paint while drying.