Many people don't realize their water contains dissolved minerals like calcium and magnesium, commonly known as hard water. These minerals leave film and scale on surfaces, dry out skin and hair, clog plumbing, and build up inside appliances that use water. Up to 85% of US homes have hard water, according to the US Geological Survey.  You may have hard water in your home if you notice white buildup on faucets, cloudy dishes, toilet rings, reduced water flow, or appliances wearing out faster. Laundry can feel stiff and look dull, stains become harder to remove, and your skin or hair may feel dry or coated after a shower. Water is considered soft below 60 milligrams per liter of calcium carbonate and very hard above 180 milligrams per liter. Minor issues can be managed with filtered showerheads or hard-water-specific detergents and shampoos designed to handle mineral residue. Severe problems may require whole-house softeners, plus regular cleaning with vinegar or acidic cleaners to prevent and remove mineral buildup.