Intentionally raising CYA to lower ph ceiling

I am not a big believer in Borates, but you might want to consider them.

They also help lower the Carbonate alkalinity.

Borates and Adjusted Alkalinity.​

Adjusted TA = TA – (CYA X CYA C.F) – (Borate x Borate CF)

Borate C.F (correction factor) based on pH.

pH.......CF

7.2.....0.051

7.4.......0.0786

7.6......0.1248

7.8......0.1989

Cyanuric Acid correction factor based on pH.

pH........CF

7.0.......0.22

7.1.......0.24

7.2.......0.26

7.3.......0.28

7.4.......0.30

7.5.......0.32

7.6.......0.33

7.7.......0.34

7.8.......0.35

7.9.......0.36

For example, if the pH = 7.6, TA = 90, Borate = 50 and CYA = 70, the adjusted alkalinity is 90 - (70 x 0.33) – (50 x 0.1248) = 60.66.

I do have Borates at 50. I read about that last year and made the addition. Thanks.
 
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I do have Borates at 50.
That should lower the Carbonate Alkalinity enough.

You are probably just worrying too much at the higher pH levels.

If the CSI is good, don't lower the pH.

Maybe get a pH meter to be really sure.

If the pH is below 8.3 and the CSI is below +0.2, then you should just leave the pH where it is.

Many people read the higher pH values as higher than they really are.

Most people over worry about higher pH when they could just leave it alone and do nothing.

Show your pH test and what you think it is.
 
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That should lower the Carbonate Alkalinity enough.

You are probably just worrying too much at the higher pH levels.

If the CSI is good, don't lower the pH.

Maybe get a pH meter to be really sure.

If the pH is below 8.3 and the CSI is below +0.2, then you should just leave the pH where it is.

Many people read the higher pH values as higher than they really are.

Most people over worry about higher pH when they could just leave it alone and do nothing.

Show your pH test and what you think it is.

I have pool math

If I don’t do anything for about a week the ph will rise above 8.0 (Taylor drops) and tops out around 8.2 with a handheld digital ph meter.

At ph of 8.2 the CSI is essentially perfect and close to zero. I would love to just let the ph ride at 8.2 but I’ve never felt confident to do that based on things I’ve read online saying you shouldn’t leave the ph that high.

Does CSI trump everything else?
Is it possible for anything to go wrong if the CSI is normal?
 
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I would love to just let the ph ride at 8.2 but I’ve never felt confident to do that based on things I’ve read online saying you shouldn’t leave the ph that high.
I would let it sit at 8.2 as long as the CSI was good.
Does CSI trump everything else?
Everything?

No.
Is it possible for anything to go wrong if the CSI is normal?
It is not a magic number, but it does a pretty good regarding scaling and plaster protection.
 
Some reports I’ve read say high ph can be bad for metal. Can a ph of 8.2 damage metal if the CSI normal?
8.2 is not high.

In my opinion, it is not going to harm any metal.
Maybe I need to better understand what CSI actually means.
Basically, the saturation of calcium carbonate is based on the molarity of the calcium ions x the molarity of the carbonate ions.
 
80-90
Some reports I’ve read say high ph can be bad for metal. Can a ph of 8.2 damage metal if the CSI normal? Maybe I need to better understand what CSI actually means.
Low pH causes corrosion.
Low CSI can cause the pool water to pull calcium out of a plaster pool.
High CSI can cause scaling in any pool, and in the SWG.
 
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The Ksp (solubility product constant) for calcium carbonate (CaCO3) is typically around 3.3 x 10^-9.

This value represents the product of the ion concentrations (Ca2+ and CO32-) when the calcium carbonate is in equilibrium with its saturated solution.

The Ksp value can vary slightly depending on the specific form of calcium carbonate (calcite or aragonite).
 

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