CSI a little out of range due to temperature?

[CombatYoga]

I haven't been entering in the temperature of the pool water into pool calculator.
With it being so cold lately, my pool temp has dropped down to 50 degrees (a little below actually).

What's interesting is that my CSI is now too low and out of range, but my chem readings don't seem too far out of line
(at least to me).

FC 3.5
CC 0
TC 3.5
ph 7.4
TA 80
CH 260
CYA 65
Salt 3300 ppm
pool temp is 50 degrees

CSI according to pool calculator is -0.78.

Anything to be concerned about here? If so, which of the chem readings should I affect? Should I raise CH a bit?

Thanks,

Slade

 

[JasonLion]

You want the PH to be higher during the winter than it is during the summer. As the water cools the PH will naturally go up on it's own, keeping everything in balance. You should raise your PH by about 0.3 or 0.4 now, and then keep it 0.2 to 0.5 higher than normal as long as the water is below about 55 degrees.

 

[CombatYoga]

Thanks a lot Jason.

I had recently added some acid to bring the pH down. I'll let it stay higher while it's cold as you suggest.

After your post, I began playing around with the pool calculator numbers. pH seems to have a heavily weighted impact on CSI (more so than temp).

Slade

 

[chem geek]

pH is the largest factor by far for the CSI. The TA is next, then CH, CYA and temperature. pH is already on a logarithmic scale which is why small changes have a big effect. For TA and CH, you have to double their values for a 0.3 change. CYA has an indirect effect on TA.