Reducing Cl


LifeTime Supporter
Jun 4, 2007
What is the best way to reduce the Cl in a pool without messing up the water chemistry? My Taylor test kit book talks about Sodium Thiosulfate Hydrate-5 being used to reduce Cl levels but I'm not exactly sure what that is and if it affects pH, alkalinity,.... Does this have a more common name or is it in a more common form?


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
Sodium Thiosulfate is sold as chlorine neutralizer, see for example here. It would tend to increase PH a little. It is ocasionally difficult to find because it is rare to need to reduce the chlorine level, it is fairly expensive, and sun light normally takes care of lowering chlorine levels without any chemical assistance.


TFP Expert
LifeTime Supporter
May 30, 2007
South Carolina
MikeInTN said:
mas985 said:
Or get your whole family to pee in the pool. :-D!!!!!!! :lol:

What! The ChemGeek thread?:whip: .........
............but you know, a lot of folks did not have the opportunity to view that...:poke:

....and you know everybody needs a good laugh! :wink: