Descaling. Dilute 1 or 2 tablespoons of citric acid in 1L of cold water and use this solution to descale coffee machines, kettles, cups, taps, showerheads and more Rinse with clear water afterwards. Remove limescale - Remove limescale from your washing machine, put 6 to 8 tablespoons of acid in the drum and run on a cycle (90°C) Toilet bowl cleaner - Pour half the bag into your toilet and leave overnight. General household cleaning - Replace vinegar as a cleaner throughout your home.