The most widely used, time-tested and “proven” swimming pool water treatment method is liquid chlorine bleach, commonly referred to as “liquid chlorine” or “bleach.” The technical name for bleach is “sodium hypochlorite.” Typically, the bleach is sold at swimming pool supply stores in refillable, plastic jugs. For most residential swimming pools, liquid chlorine bleach is the swimming pool water treatment of choice due to its proven effectiveness, safety, convenience, low cost and the fact that when used regularly, it gives the swimming pool water a beautiful, visually “sparkling” clarity that is unmatched by any other method.
Liquid chlorine bleach is an extremely effective sanitizer, capable of killing bacteria and viruses. (4) (5) Liquid chlorine bleach for swimming pool applications usually contains 10% available chlorine. The relatively low concentration of available chlorine in bleach makes bleach one of the safest forms of chlorine for swimming pool use.
Chlorine gas also is an effective sanitizer but it can be hazardous to store, handle and apply. It is usually used only in large commercial pool applications that have equipment to continually monitor chlorine concentrations and inject chlorine as needed to maintain the chlorine levels. This involves the installation and operation (by qualified personnel) of sophisticated monitoring and application equipment that are impractical for most single family, residential swimming pool applications.
Solid forms of chlorine are available in the form of calcium hypochlorite or trichlor, commonly sold as “tablets”. When used in conjunction with liquid chlorine bleach, tablets are useful as a supplement to help maintain chlorine levels in between regular (typically once per week) applications of the liquid chlorine bleach. However, calcium hypochlorite is reactive and when combined with organic compounds can become explosive. (4) Because of its reactive nature, the storing of calcium hypochlorite by untrained individuals can be hazardous and is not recommended. For example, storing calcium hypochlorite in a tool shed where there may be oily rags or gasoline, or where moisture can get into the tablets, can create chemical reactions which, in turn, could result in a fire and the release of chlorine gas. (5)
The relative safety, proven effectiveness, convenience and low cost of liquid chlorine bleach makes it the most popular and preferred method for chlorinating residential swimming pools.
Liquid Chlorine Bleach: Other Pool Chemicals Needed Maintenance Requirements Long Term Costs