Can M-Acid loose its powers??

[partypond]

My pH has been high this week and normally I can treat it once a week and it stays managable. This week I have added Muratic acid everyday and just cant get it to come down at all. I have been adding more than recommended by pool calculator. My pool is about 5 months old and this is a new problem. So I was wondering if maybe it is the acid and not the pool. Can the acid go bad?? I keep it in the garage and yes here in Texas the temperature has been over 100 for almost 40 days now. Could that be my problem? THANKS!

FC 6
CC 0
pH 7.7 to 7.8 (usually sits about 7.5)
CH 600 (yes high but always been that way)
CYA 60
TA 70

 

[DBfan187]

AFAIK it has an infinite shelf life

 

[linen]

Unlikely...how much do you typically add to change pH by how much?

 

[stev32k]

Hydrochloric acid aka MA does not have a shelf life. It will maintain it's strength indefinitely if kept in a closed container. You might check the strength of the acid you have vs what the pool calculator says and see if they match. If the pool calculator is using 31% for it's calculation, but you are using 15% that might be a problem.

 

[partypond]

UPDATE - after going through half the bottle and not being able to get my pH down I finally just bought more, added it and now everything is fine. I have no idea what happened but that bottle was bad. Lesson learned and now my ph is right where it needs to be.

Thanks for the input.

 

[mas985]

My pool is about 5 months old and this is a new problem.

36x16 gunite

Two factors that will usually mean rising PH. It takes some time for the surface to cure and while it does, PH rises, TA rises and CH rises. It might have been bad acid but it may not be over either.