Limescale is a chalky deposit that mainly contains a build up of calcium carbonate. If you have been noticing white spots/stains in your shower, they are most likely limescale stains. Limescale is caused by tap water. Filtered water helps to get rid of chemicals and limescale from being in your water. To clean the limescale stains off of your shower, you can use lemon juice and scrub the stain until it goes away.
