What is free chlorine?
Every sanitizer has two key functions, to sanitize (kill bacteria and all living organisms) and also oxidize (destroy contaminants and waste). The most popular pool and spa sanitizer is chlorine. Chlorine is also classified as a disinfectant, meaning that it is capable of killing bacteria, algae and other organic material instantly. All chlorine does the same thing when it is added to the water, regardless of the type of chlorine added. It forms free available chlorine. Free chlorine is the form of chlorine that kills bacteria, algae and disease-causing organisms. You must maintain free chlorine at a sufficient level to disinfect potential contaminants on contact. The more chlorine in the water, the more it can sanitize and oxidize the water. (Remember that sanitizing and oxidizing are the processes that chlorine uses to keep the water clear and clean.) However, if the free chlorine level gets too high, it can make the water uncomfortable for swimmers.
