Lime deposits are not just a nuisance because they leave a thin greyish-white layer on tiles, shower walls and fixtures. They can also destroy electrical appliances. “On surfaces exposed to hot water, limescale can build up particularly rapidly,” says Bernd Glassl of the Industrial Association for Personal Care and Detergents (IKW) in Germany. The harder the water – meaning the amounts of dissolved calcium and magnesium in it – the more calciferous or chalky it is. And the hotter the water the faster the calcification process. This can become a problem for household appliances that use water. …