TA and pH balancing act

[ciaka]

Following y'all recommendations, O have been using liquid chlorine and MA to balance FC and pH.
What I noticed that at TA of 100 and higher, my pH was rising quicker. So the higher my TA, the sooner I had to add more MA to water, to bring pH down.
After reading more on this relationship, I decided to bring TA down to 75, by adding MA (enough to bring pH down to low 7s). Them I would aerate water (aka turn on any water features I had), so air bubbles were going into pool to aerate it. This in turn brought my pH up, without affecting TA.
Once my TA reached 75, my pH ruse has stabilized. Last time I added MA was 5 days ago, and as of yesterday, my pH was still identical. Coincidentally, my FC also stayed same but I did increase chlorinator setting by one (from 4 to 5), while I am adding cya via tabs.

I'm sure you fine folks lnow this well already.
However here is my inquiry.
Without experimenting and watching trends, how could I have known what to do with TA? Is there someone known TA limit that one needs to go under to reach this balance? Or is it simply treat, observe, treat more, observe more, to eventual reaching this balance between TS and pH?
Wanted to understand this more than just "it worked, so just leave it alone" approach.
Thanks.

 

[Oly]

Test your fill water for TA. Adding acid will lower your TA over time. Once your TA is in range your pH will stabilize until you add more water assuming your source water is high in TA. Best to watch your CSI, calcium saturation index, and use it to guide your water balance.

 

[Mdragger88]

Every pool is a little different - each one has a TA it likes as noted by the ph stability. This is why the Recommended Levels is a range instead of just telling everyone that 70 is perfect since that isn’t suitable or practical for everyone .
Glad you have possibly found your pool’s Happy TA ! Some aren’t as lucky & struggle w/ rapid ph rise as a result of their fill water, plaster etc.
I am quite lucky here that I seem to be able to adjust ph/ta @ the beginning of the season & it stays the same until i close.
Happy Pooling!

 

[ciaka]

But without trial error, how would I know my TA range?
Just trying to understand if I could have gone and did something to start off, and eliminate the trial error time and money.
Is the range 75 or less?
Or is the best ta range different for each pool, and how would one know the best TA range to begin with. Thanks.

 

[Oly]

Yes every pool is unique and testing will help you understand yours. Knowing your fill water is important. Dial in your water chemistry with the CSI.

 

[aussieta]

my pool settled on ta 50
every pool is a little different
basically dont add bicarb unless ta goes under 50
as you keep your ph in range your pool should find its sweet spot, no need to rush it unless csi is excessive
if you have high ta fill water you will always struggle a little

 

[ciaka]

I don't know how to balance water with csi yet

 

[Oly]

Pool Math will calculate CSI. Be sure to add all the actual test results including water temp and salt ppm.

 

[Mdragger88]

You should only lower ph to 7 so if your ta was really high (100+) you can’t add enough acid safely in one go to accomplish a 70 or 80 ta . Therefore it must be done in steps. Its not trial & error so much as a process that will show u when you are balanced by the reduction in ph rise. Some with lower ta’s can accomplish this in days with others its a longer process.
its all detailed here

Lower Total Alkalinity

A lower Total Alkalinity level can help a pool owner stabalize their pH increase. We'll explain how to lower TA with a little help from muriatic acid.

www.troublefreepool.com

 

[ciaka]

That was one of the articles I read on the topic.
Looks to me that knowing that reducing TA, will reduce pH swing, one would have to start at high end of TA, and incrementally lower it with MA, then aerate to bring pH up, to repeat process, until pH doesn't swing up quickly anymore.
Surely sounds like trial/error. Not that there is anything wrong g with trial error, I was just wondering about whether the balancing can be achieved quickly. Since pH shouldn't be lowered way down lower than 7s, I can definitely see how this incremental process would need to run its course.
Well, looks like my pool is reaching this equilibrium. I will test again tomorrow to see how things are holding up TA and pH wise.