I had a pool guy that was using pucks and my CYA went up to 78 (per a test at Leslies). I let him go and I'm doing it myself using liquid chlorine. My problem is the day I had Leslies test my water they said my TA was 48 (adjusted because of the CYA) My other readings were Free Chlorine 5.27. PH 8. Total Alk 48 (adjusted due to CYA) They had me increase TA and decrease PH which I did. OK - so now I test daily. My chlorine is usually around 4.5 in the morning and I add about 24 oz of liquid chlorine. My PH seems to always raise to 8.0 - I add 9 oz MA and the next day it will be 7.8, but then the second day goes back to 8.0 again. My TA is 80. My CYA is still 78-80 (hard to tell with the taylor kit - that little dot drives me crazy). I don't understand why I have to keep adding Muriatic Acid. I live in Tucson (hot and sunny) - it's been extremely windy for weeks - I have a new Stonescapes surface (January 2023). Do any of these affect the PH? Are my other readings OK? In the booklet with the Taylor test kit there is a Table relating to CYA correction to Total Alk. but I don't understand it. Like I said I need HELP!!!
I need help understanding if my CYA is affecting my PH and TA
- Thread starter KTaylor49
- Start date
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- May 28, 2020
- 1,212
- Pool Size
- 13000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Try making bigger corrections to pH so that your TA comes down some when you add acid. When pH gets to 8, lower it to 7.4. TA acts as a pH buffer, and when you lower it a bit more, pH will start to stabilize better.
49,
The CYA does not really effect the TA or pH, is it just a different way to measure TA.
Thanks,
Jim R.
The CYA does not really effect the TA or pH, is it just a different way to measure TA.
Thanks,
Jim R.
- Jun 24, 2021
- 7,503
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60
With a new pool surface, you will experience a higher level of pH rise. This will last for 6-24 months after installation.
So my TA according to my taylor test kit is 80. but if I adjust based on CYA it would be like 26. Do I need to raise it? That is what I'm confused about
- Jun 24, 2021
- 7,503
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60
You pool is going to raise your pH on an ongoing basis for 6-12 month.
Ignore TA. Your TA is fine.
Manage pH. When it gets to 8, reduce to 7.6. Rinse and repeat.
Ignore TA. Your TA is fine.
Manage pH. When it gets to 8, reduce to 7.6. Rinse and repeat.
Is this exclusively for masonry pools? Or do fiberglass and vinyl pools experience this as well?
49,
We do not use the "adjusted" TA measurement like pool stores. All the TFP TA numbers you see are based upon the Taylor drop tests, without any adjustment for CYA.
If your Taylor kit measures 80, you are perfect.
Thanks,
Jim R.
We do not use the "adjusted" TA measurement like pool stores. All the TFP TA numbers you see are based upon the Taylor drop tests, without any adjustment for CYA.
If your Taylor kit measures 80, you are perfect.
Thanks,
Jim R.
Thanks, Jim, we were having a little trouble answering the question until you cleared it up. 
- Jun 24, 2021
- 7,503
- Pool Size
- 30000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60
- Mar 5, 2020
- 3,034
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
Total Alkalinity is called Total Alkalinity because it's Total Alkalinity.
The CYA contribution to Total Alkalinity is real Alkalinity and contributes to a pool's pH buffering.
The other main contributer to TA is Carbonate Alkalinity, which can be calculated from TA by subtracting about 1/3 (exact value is pH dependant) of the CYA reading.
The Carbonate Alkalinity value can be used to calculate how much Carbonate is in the water, which can then be used (together with other parameters) to calculate if the water is at risk of forming Calcium Carbonate scale or "pull" it out of plaster surfaces. This is the only time where TA needs a correction for this specific calculation purpose.
No one does these calculations by hand anymore, and calculator apps like PoolMath expect the full TA value as measured with the test kit to be entered. It does the correction internally to calculate the Calcium Carbonate saturation.
There is absolutely no reason why the Carbonate Alkalinity value should be made visible as "adjusted" Alkalinity to the pool store customer or app user, apart from creating confusion and make TA look lower to use that as a marketing instrument to sell more overpriced baking soda.
The CYA contribution to Total Alkalinity is real Alkalinity and contributes to a pool's pH buffering.
The other main contributer to TA is Carbonate Alkalinity, which can be calculated from TA by subtracting about 1/3 (exact value is pH dependant) of the CYA reading.
The Carbonate Alkalinity value can be used to calculate how much Carbonate is in the water, which can then be used (together with other parameters) to calculate if the water is at risk of forming Calcium Carbonate scale or "pull" it out of plaster surfaces. This is the only time where TA needs a correction for this specific calculation purpose.
No one does these calculations by hand anymore, and calculator apps like PoolMath expect the full TA value as measured with the test kit to be entered. It does the correction internally to calculate the Calcium Carbonate saturation.
There is absolutely no reason why the Carbonate Alkalinity value should be made visible as "adjusted" Alkalinity to the pool store customer or app user, apart from creating confusion and make TA look lower to use that as a marketing instrument to sell more overpriced baking soda.
Are you saying that there is no reason to adjust alk for high cya if you are in a vinyl pool?
- Mar 5, 2020
- 3,034
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
Keeping pH in the 7s still applies.
When chlorinating with trichlor on a permanent basusy, you should keep TA above 80. Even at higher CYA around 80ppm there should still be enough Carbonate Alkalinity to have enough CO2 outgassing to compensate the pH drop by constantly adding Trichlor. At higher CYA (even earlier), when TA starts to get dominated by CYA, you need to reduce CYA anyway to be able to maintain a reasonable FC/CYA ratio. The pool store advice of maintaining TA 100-120 and adjusting Alkalinity is double dipping.
TFPs recommended levels apply to liquid chlorine or SWG pools.
When chlorinating with trichlor on a permanent basusy, you should keep TA above 80. Even at higher CYA around 80ppm there should still be enough Carbonate Alkalinity to have enough CO2 outgassing to compensate the pH drop by constantly adding Trichlor. At higher CYA (even earlier), when TA starts to get dominated by CYA, you need to reduce CYA anyway to be able to maintain a reasonable FC/CYA ratio. The pool store advice of maintaining TA 100-120 and adjusting Alkalinity is double dipping.
TFPs recommended levels apply to liquid chlorine or SWG pools.