There’s a reason chlorine is such a basic part of regular swimming pool maintenance. It performs a half-dozen vital services without requiring lots of work on your part, and at a very reasonable price. Chlorine is a basic element that is normally very stable in nature. That’s because it readily combines with sodium to form salt, or with itself to form Chlorine-Chlorine molecules that are not very reactive. But mix it with water and those individual chlorine atoms float around freely as something called ions. Those ions are very active indeed.

They love to kill germs, algae, bacteria, and other potentially harmful critters that would otherwise populate every pool. That keeps your pool safe for swimmers.