PH Levels - time of day

joemkraus

Well-known member
Sep 23, 2019
80
Saratoga, CA
My PH levels measurements vary widely as per the time of day. EG. in the morning when the pool filter has not run for 12+ hours I get almost and 8.0, but in the evening, while pump has run all day and is still running, I get around 7.5.
I tend to believe the evening one as when I put in MA is seems to effect the evening one appropriately.

Is this due to the water standing all night? Curious, as never thought it would make much difference
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
34,475
Sebring, Florida
pH does NOT vary like that. I don't yet know what the issue is but pH does not bob up and down.

in the morning when the pool filter has not run for 12+ hours I get almost and 8.0
Never take a pool sample when the pump has not been running for 30-60 minutes prior to the test.
 

joemkraus

Well-known member
Sep 23, 2019
80
Saratoga, CA
Pool is not covered, and I agree with the comment about the pH should not very. Every night when I measured it is consistent and only changes very slowly but for some reason in the morning it registers higher. OK, I don’t know why the pool pump Hass to be running but I will take your word for it as I said in the pool runs all day and I take the reading in the evening it is consistent. Are you also saying that all test should be done at the pump has been running? I just assumed overnight that it was all mixed up accordingly but maybe I should just do my FC test in the evening also
 

proavia

LifeTime Supporter
TFP Guide
Feb 6, 2015
2,037
Chandler AZ
Pool Size
12300
Surface
Plaster
Chlorine
Liquid Chlorine
Pool pump has to be running for 30 minutes or more so the water is well mixed. Take a sample from about 18" underwater and from the same physical location each time.