To descale your kettle, just pour in about a tablespoon of citric acid and an inch of water, switch the kettle on and watch as the acid fizzes away working its magic. Turn the kettle off before it reaches the boil, and repeat until there’s no more limescale left. Then rinse your kettle out a couple of times before using it again. You can also use citric acid to clean limescale stains on toilets, cloudy glasses, showerheads and more - read the instructions on the manufacturer’s website for full details.