Chlorine degradation due to heat over time

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
San Rafael, CA USA
Thanks. That's a nice chart and seems roughly consistent with the table at the end of this link. The half-life (50% loss of concentration) of 12% bleach at 90ºF would be around 80 days or 11.4 weeks which is a little better than the projected 9 weeks in the chart, but the Odyssey product is supposed to be of high-quality mostly free of metal ions so that it lasts longer.


Well-known member
Aug 25, 2012
Melbourne, Australia
Is there any way to test chlorine concentration at home?

Other than using the pool calculator and discovering you have a weak batch of liquid chlorine/bleach!