Do you hate soap scum? It may be due to hard water. Hard water is water that is high in mineral content, particularly calcium and magnesium. If you have hard water, soap will not lather as easily. This causes soap scum to be more prevalent and if the water contains iron, you may see rust staining. Hardness in water varies by region. Those in New England tend to have lower water hardness, while those in Southern California may have harder water. Many people install water softeners to help alleviate this problem. The softeners make the water softer feeling and allow laundry detergents and soaps to lather more effectively.