Historically, chlorine has been used the longest in the spa industry and it tends to be popular due to its ease of use and lower cost. It is an effective means for sanitizing spa water and killing bacteria. Granular chlorine can be applied directly to spa water to protect bathers against contaminants. Chlorine can be stabilized against UV degradation, so it is often the ideal choice for outdoor spas that are exposed to sunlight.

  • Granular chlorine has a more neutral pH – With a pH closer to neutral your water is more likely to stay in balance which allows for less chemical applications.
  • Chlorine can also be used as an oxidizer – Chlorine is excellent at oxidizing compounds in spas, which tend to accumulate in these small bodies of water with higher bather loads
  • Chlorine is more compatible with certain ionizing cartridge systems – Some manufacturers endorse the use of chlorine with their systems for maximum effectiveness