Individual values in range, but CSI is low - recommendations?

[lhlsea]

Hi all, as I head into essentially my first winter taking care of our pool I wanted to see if you had recommendations for how to adjust my water. Here are my current results:

FC 12.5 (I don't normally keep it this high, I just had to temporarily use some tablets and it went higher than I thought it would)
pH 7.5
TA 70
CH 250
CYA 45
CSI -0.50
TEMP 60

My CSI was much closer to zero throughout the summer with a pool temp around 84 and a pH of usually 7.8.

I think all of my values are individually in range, but wanted to see which dials you recommend I turn to get my CSI back closer to zero (assuming you agree I need to).

Thanks!
-- Lewis

 

[JamesW]

I would let the pH go back up.

 

[JoyfulNoise]

Is this pool staying "open" over the winter?

If so, you can let the pH rise to 7.8 and let it hang out there. There's no reason to keep a cold pool at low pH and that will have a big impact on CSI.

 

[lhlsea]

Is this pool staying "open" over the winter?

If so, you can let the pH rise to 7.8 and let it hang out there. There's no reason to keep a cold pool at low pH and that will have a big impact on CSI.

Thanks! By “open” do you mean people swimming in it? It won’t be used or heated, but It will remain full, pump on, etc throughout the winter (we are in Seattle).

 

[JoyfulNoise]

Thanks! By “open” do you mean people swimming in it? It won’t be used or heated, but It will remain full, pump on, etc throughout the winter (we are in Seattle).

That’s what I was thinking - it’s open just not swimmable. You should let the pH drift higher in the winter as cold water has a lower CSI than warm water when all other parameters are equal.

 

[lhlsea]

That’s what I was thinking - it’s open just not swimmable. You should let the pH drift higher in the winter as cold water has a lower CSI than warm water when all other parameters are equal.

Gotcha. Thanks!