Which chemicals to work on next…

[UnderwaterDogg]

Hello!
First pool season here. I have the chlorine and CYA under control, more or less. Still figuring out the percentage to have the salt cell operate at, and slowly bringing up my CYA level to around 40. (We have an autocover, so I think that level is ok?) Anyway, kind of wondering what to do next. My TA is quite high, 260. Ph has been a little hard for me to read in the comparator block. I *think* it’s at 7.8 but it’s hard to say, it might be higher. The colors just dont look quite right. I think I should drop the pH a little regardless. Which chemical should I work on next? Is there something more important to address? Thank you so much for any insights you have for me!

 

[IceShadow]

Try four drops instead of five with the pH test. See if that makes it any better.

TA will come down as you add acid to control pH. What is the TA of your fill water?

 

[UnderwaterDogg]

Ok, I’ll try the four instead of five drops. The test is still legit when you do that?
The total alkalinity of my water has been testing at about 260.

 

[IceShadow]

Ok, I’ll try the four instead of five drops. The test is still legit when you do that?
The total alkalinity of my water has been testing at about 260.

Yes - it’s about the shade. Some find the lower intensity of the color makes for an easier match.

What is the TA of the water you use to add water to the pool, like to replace evaporation? What are you using to test?

 

[UnderwaterDogg]

Try four drops instead of five with the pH test. See if that makes it any better.

TA will come down as you add acid to control pH. What is the TA of your fill water?

I just tested now. It is about 280. We are on a well. Our well water was the primary source of the initial fill.
I am using the TF Pro test kit.
I will try the four drop test tonight after work.

 

[IceShadow]

OK, sounds good. The high TA of the well water is going to mean your TA will be rising whenever you have to add more water to fill, after backwashing, etc.

The pH will rise with aeration - probably rather quickly at first with that high of a TA. You will be adding acid to bring down the pH, and as you do, it will slowly decrease the TA.

So - acid additions lower TA. Water additions raise the TA. Ultimately the pH is what you need to keep an eye on, and add acid as needed - when the pH hits about 8.0, you add acid to bring it down to 7.4 - 7.6 or so. Each time you want to add acid, check the current TA of the pool to see what it is, as that will affect how much acid has to be added.

If you want to limit the TA rise to try and limit the acid additions, you want to do what you can to limit adding water to the pool from the well. Mostly that means trying to avoid evaporation and addressing any leaks quickly. The autocover will help with that - I would certainly recommend keeping that closed at night.