TA and PH Balancing Questions

shawnp40

Member
Sep 19, 2018
8
Baltimore, MD
I have been using the BBA method now all summer. Works like a charm.
No more pucks; all liquid chlorine for me here on out.
My CYA is higher than I like (due to pucks) but I maintain FC pretty consistently using the TFP tables.

Pool = 25k Gallons, Plaster Inground with Spa Spillover and Waterfalls
CYA=103
FC = 8.2
pH = 8.1
TA = 65
TH = 364

I have added 36oz of Muriatic Acid each week and yet the pH seems to keep rising to around 8-8.2.

Question 1: Should I worry about my TA being low, from everything I read it should be a little higher like 70-90 thus I should consider adding 5-10lbs of baking soda?
Question 2: My pH keeps rising quickly (presumably, due to low TA and the fact the spillover (aeration) runs daily from spa). Should I keep maintaining weekly with MurAcid, or fix TA first?
Question 3: My TH is high but there is nothing I can do about it but replace water, which is probably something I should plan due to my CYA being high as well, correct?

Thanks for all the support TFP friends. I feel so much more confident with my pool these days!
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,929
NW Ohio
Those numbers look quite suspect. If you aren't testing your own water with a Taylor k-2006c or TF-100 kit then it is highly recommended you order one. Accurate numbers are key to good pool management.

To answer your questions:

1 - No. Typical TA recommendations assume using pucks, which are made of highly acidic trichlor. Higher TA offsets this. When using liquid chlorine, a relatively neutral pH source of chlorine, the TA has to be lower to maintain a more level pH. That's why we recommend as low as 50 TA. See the Recommended Levels Page

2 - pH rises quickly because of high TA, not low. Keep using acid and allow your TA to drop. Again though, I don't particularly trust those results.

3 - We don't really worry about Total Hardness, it is the Calcium Hardness we worry about. For a plaster pool a CH of 250-350 is good, so this number is likely well within line. If those numbers are accurate and most of that TH is calcium. I know, broken record, but reliable test results are a must for more specific guidance.
 

shawnp40

Member
Sep 19, 2018
8
Baltimore, MD
Yes I use a Taylor2006 kit.
And great, I will not mess with the baking soda.

I will add more acid again. Maybe my acid was old (I think I used a bottle I had left over from years ago).
The acid did not seem as effective as it should have.
I bought a new bottle today. Will add and test water tonight and reply back with results.

Do I understand correctly, that each time I add acid it will reduce TA as well?

Great information and yes all the numbers came from my Taylor kit. I took a water sample in to be sure.
They said my TA was a lower than I tested (I tested at 80, they said 65).
They said my FC was lower than I tested (I tested 10, they said 8.2).
They said my CYA was higher than I tested (I tested 85, they said 103).
pH and Hardness was same at home and in store.

Thank you for such a quick reply.