What type of chlorine is most commonly used in swimming pools?

Calcium hypochlorite is the most commonly used form of chlorine in swimming pools due to its effectiveness, stability, and ease of use. It is a solid compound, often in granular or tablet form, which provides convenience for dosing and application. When added to water, calcium hypochlorite dissolves to release chlorine, which then works as a strong oxidizer to sanitize the pool by killing bacteria and eliminating organic contaminants.

Additionally, calcium hypochlorite has a high available chlorine content, usually around 65-70%, allowing for effective disinfection with relatively low dosages. Its stability is another key factor, as it can be stored for extended periods without losing potency, unlike some other chlorine forms that may degrade more quickly.

Other options, while useful in specific contexts, either do not have the same level of availability or effectiveness as calcium hypochlorite. For instance, liquid chlorine is effective but has a shorter shelf-life and can be more hazardous in handling. Trichlor is often used in tablet form primarily for continuous feeding but has a lower chlorine concentration and can lead to cyanuric acid buildup. Bleach, while a source of chlorine, typically has a lower concentration and is not formulated for pool use, which can make