Can't get pH to stay in the 7s

[joecooler]

Per subject, the pH of my tub very stubbornly wants to be at 8.2. I've added pH decreaser multiple times and it will drop down to the mid 7's but creeps back up to 8.2 w/in a few days. The water feels and looks great so I'm wondering if I can just leave it where it is; if not, any idea how to get it to stay in the 7's?

 

[Wobblerlorri]

What kit are you using for testing? Please post results in the format

FC
CC
pH
TA
CH
CYA

Your problem is likely caused by a TA that is not balanced. TA and pH go hand in hand.

Please read the following articles

ABCs of Pool Water Chemistry

Table of Contents

List View Pool Care basics Algae Pool Equipment How To Pool Construction Miscellaneous

www.troublefreepool.com

To see how we do things around here.

 

[joecooler]

I am using the TF Testkits gear ... the Taylor drop tests and also the pH meter sold at TF. I've read all the articles, multiple times. :-D Here are my numbers:

FC - 2.5
CC - 0.5
pH - 8.2
TA - 60
CH - 150
CYA - don't know, don't measure it

TA and CH have been rock solid since I filled the tub at the end of April. Per my sig, I use a SWG and FC has been reliably in the 1-3 range, as I would expect based on the system I'm using. Only issue has been the pH. Spa is outside and covered.

 

[joecooler]

Any ideas, anybody?

 

[ajw22]

If you run the bubbler a lot then aeration will raise your pH.

Needing to adjust the pH every few days is normal.

 

[Nigel459]

Upon a fresh fill my spa pH will drift up, faster with aeration (jets) on, and require adjustment at first as well. My fill water is TA ~150.

I use the acid demand test and MA to drop ph to ~7.2. Takes a number of times, and each time TA drops a bit. Once my TA gets down to 50-60, my PH settles in at ~7.7 for me and won’t move.

So keep at the adjustments till your TA gets to a point where things are balanced and pH is stable. Of course there’s a technical chemical reason, I think it has to do with CO2 off gassing if you’re interested in searching for it.

Cheers

 

[Oly]

As mentioned above, if you are using the jets that will drive your pH higher.
Use MA to lower your pH and keep it below 8.
Do test your pH with the your drop test to confirm you meter is calibrated properly.

 

[joecooler]

Since my TA is already 60, do I need to worry about bringing it down even lower?

I actually bought a calibrating solution off Amazon as I don't totally trust the meter, but actually it has been pretty reliable on follow-up calibration tests.

 

[ajw22]

Let the TA come down as you lower the pH.

 

[joecooler]

OK thanks I'll keep working it.

 

[Nigel459]

Ya I bet you need to drop your TA juuust a bit more... they say to be careful mich below 50