Hard water is water that has a high mineral content, such as calcium and magnesium. While it’s not considered dangerous to safety or health, it can create costly maintenance problems in the home. The most effective way to solve hard water problems is by installing a water softener.
Often the straps that secure the pipe leading to a shower-head become loose creating an annoying rattle as the shower is pressurized. To alleviate this without tearing into the wall to re-secure the pipe, try using expandable foam.