Hard water is a problem in 85% of American homes. Hard water contains high levels of calcium and magnesium. Water hardness is measured in GPG (grains per gallon). Even if you don’t live in a “very hard” or “extremely hard” water zones, you may start to see the effects of hard water at around 7 grains of hardness.
Hard Water VS. Soft Water - Soap scum & build up on your shower heads and faucets
There are several telltale signs of hard water
Hard Water Problems - dry hair & skin, soap scum & build up