Soap scum or limescale is a filmy layer that forms around showers, sinks, tubs, and other areas where soap and water are often present together. It is caused by the minerals that are naturally present in water. When these minerals combine with soap, they create a sticky mixture that adheres to surrounding surfaces, slowly creating a scaly buildup that may also include body oils, dead skin, hair, and dirt. For many people, soap scum is a regular cleaning bugbear, especially if they live in areas with hard water.
Regular soap scum is white to gray in color, but it often acts as an ideal substrate for algae and molds, and it may develop a rainbow of colors along with some undesirable odors. When limescale is allowed to build up to this point, it can also become very difficult to remove. Only heavy scrubbing and a strong cleaner will be able to penetrate the layers.
Most people are less interested in knowing what soap scum is and more interested in knowing how to get rid of it. The best way to deal with it is to clean regularly, preventing the buildup from becoming firmly adhered. Wiping down tubs, showers, sinks, and tile at least once a week can often keep soap scum to a minimum, especially if ammonia or vinegar is added to the sponge or cloth used for wiping, as these substances will cut through the layers. Detergent can also remove it. Wiping down a tub after using bath oils is also highly recommended.
Some people use wax and other products designed to increase water resistance to reduce soap scum by preventing the deposition of water on the walls of showers and tubs. This can be effective in some cases, but the wax can also become very messy, and it needs to be routinely stripped and reapplied.
For more heavy-duty cleaning, a commercial degreaser is often very effective against soap scum. People can also use specially formulated cleaning products or lemon juice, vinegar, or ammonia. A paste of baking soda and water can also work, with the baking soda acting as an abrasive to lift away the layers. When using heavy cleaners, people should leave a window open and wear gloves so that the cleaners do not irritate the lungs or hands.