I filled my hot tub last week and have been trying to get my pH, TA, FC, and CH to the proper levels. This is my 10th year of using this system, and I've never had problems like this. The pH reads above eight, so I added the appropriate amount of muriatic acid according to the PoolMath program. I tweak it until the pH is at 7.4 and then test the TA, and it reads around 10. I add baking soda according to PoolMath and get it to 50. Then I test the pH, and it's way above eight again, so I start the cycle all over. This has been going on four to five times a day for the last week. I've gone through about 20+ ounces of muriatic acid and about 20 ounces of baking soda. The good news is that the FC and CH have been good since day one. Any ideas on how to get the pH and TA balanced, or should I just shoot for a pH of 7.4 and forget about the TA level? I really would like to use my hot tub sometime this season. TIA for your help and suggestions.
Can't get my pH and TA balanced properly
- Thread starter JLA956
- Start date
- Jun 24, 2021
- 15,766
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
How are you testing your water?
You want to have a TA about 50. I would raise your TA to 50. Then let pH settle. The problem you are having is because you are lowering pH too low. When you lower pH, you are also lowering TA.
With a TA of 50, your pH will likely be stable between 7.8 and 8.0. I would not lower pH below 7.8. and see if it is more stable there. Any pH in the 7s, even 8.0 is just fine.
Spa & Hot Tub Maintenance A Basic Guide
Hot Tub Maintenance can be done easy with a few tricks. Hot tub chemicals, rashes, and schedules are all covered in this easy to grasp article.
www.troublefreepool.com
I’m no expert but if I were in this predicament, I’d raise TA to 70 first and then add acid to get to 7.4.
If you aren’t using one of the test kits recommended here, then I’d disregard my advice. If you aren’t using one using strips, may God have mercy in your soul. Just a little credit to “The Green Mile” and my attempt at humor.
If you aren’t using one of the test kits recommended here, then I’d disregard my advice. If you aren’t using one using strips, may God have mercy in your soul. Just a little credit to “The Green Mile” and my attempt at humor.
- Jun 24, 2021
- 15,766
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Since spas have aeration, the TA should be lower.
Low pH, high TA, and aeration are primary causes of pH rise. When TA is lower, pH rise slows. At some point pH and TA tend to be in balance around pH 7.6-8.0 and TA of 50-80.
Advice stands...the cause of the TA/pH yo-yo with baking soda/acid is because the OP is trying to force pH to a place that it doesn't want to be. Get off the cycle. Run your TA at 50, and stop lowering pH to 7.4. Let it sit at 7.8 or so and see what happens.
PH TA Relationship - Further Reading
www.troublefreepool.com
Thanks for everyone's advice - I will work on getting the TA set and then go from there. I do notice that when I turn the aeration on, it definitely pushes the pH up. By the way, I only use the Taylor test kit - I threw the test strips out when I changed over to this method.
- Jun 24, 2021
- 15,766
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Great job on the test kit.
Let us know where your pH lands when you get TA to 50...let it settle for a few days.
Let us know where your pH lands when you get TA to 50...let it settle for a few days.
To clarify my TA recommendation of 70, I’d just get it there before adjusting the pH with the acid understanding it would drop after adding the muriatic acid. I’d want the TA to end up at 50. I’d be ok at 60. I would not want it at 70 on a daily basis.
And what I meant regarding my pH remark of 7.4 was to add whatever amount of acid the calculator said to add to get to 7.4. If your tub is like mine, it would only drop to 7.6 or so. I would want to end up running at 7.6-7.8.
My suggestions are meant to get you at TA 50-60 and pH 7.6-7.8.
And what I meant regarding my pH remark of 7.4 was to add whatever amount of acid the calculator said to add to get to 7.4. If your tub is like mine, it would only drop to 7.6 or so. I would want to end up running at 7.6-7.8.
My suggestions are meant to get you at TA 50-60 and pH 7.6-7.8.
Last edited:
JoeSelf
Gold Supporter
Let the spa sit for at least 15 minutes after jets have run to test the Ph.
I myself totally ignore my TA.
After a fill, I dose acid daily to bring the pH to around 7.2. It drifts back up, and I add more acid. Eventually it settles somewhere around 7.5. I cannot remember the last time I added baking soda to my hot tub.
Then I look at my TA and say "oh, that is where it needs to be". As long as it is not totally out of whack, I am fine with it.
5 days ago when it stabilized after my last water change, my pH was 7.5 and my TA was 50. That is cool with me and I have no desire to try to get it to some other "ideal" value.
Just this last cycle I added the step of adding 12 oz of boric acid once everything settled.
I don’t know if this applies, but I make most of my water adjustment mistakes due to my impatience. It has taken me one year and 4 water changes to start learning this. Mainly in dealing with a freshly purged new fill. I believe phonedave and mdragger88 just dispensed some wonderful wisdom. Go really slow with a new fill.
I think that I'm going to follow your advice. I have been working for weeks trying to get my TA and pH to the recommended levels and can't get them there. I measure the levels once a day and then add either acid or baking soda to adjust. I let things settle and then measure the next day. I finally gave up on the TA, as every time I added baking soda to get it to where it needed to be, then I would end up having to add two to three ounces of acid the next day to get the pH back down. Then it started all over. So, I've finally gotten my pH to 7.4, and my TA is 20, so I will just go with that and keep monitoring it. If it settles in there then I will add borates to stabilize it. Thanks for everyone's help on this.
I’m no expert but why wouldn’t you add boric acid now? Let it be doing what it does while everything is settling. Just asking.
Among other things, borates acts as a buffer for pH. It is better to get your pH and TA to a good place before you go adding something that makes it harder to move the pH.