pH and high Cl

[sande005]

So I know that Cl over ~10 prevents an accurate pH reading. I'm running high (14 ppm), just due to bumping up the SWCG prior to lots of forecast rain. And I fully intend to not do anything to the pH until the Cl drops.
But...there was a very old thread discussing diluting pool water 1:1 with distilled to test pH at high Cl.

Did that turn out to be a valid methodology? Is that something that those running higher CYA need to consider?

 

[mgtfp]

Yes, this is valid. But it's important to use distilled water, not tap water.

With distilled water having no chlorine, the dilution halves the chlorine, removing the interfere with the pH test.

And because distilled water has pretty much no Alkalinity, it doesn't significantly change the pH of your buffered pool water sample.