CSI and cold water?

[tjslice]

Is keeping the TA around 120 and pH at 7.8 an acceptable way of keeping the CSI up during the winter?

We have a pebble pool and a SWG. At the recommended levels, with a water temperature of 48, the CSI would be at -.60

My current results, after a ton of rain the last few days:

pH 7.8
TA 130
CH 270
CYA 100 (I am working on lowering this a little bit at a time)
Temp 48
Salt 2900
CSI -0.17

 

[chem geek]

The pH would normally rise anyway just from the water being colder so yes having the pH up around 7.8 is very reasonable to do. With the water colder, all chemical reactions including any dissolving of plaster is going to be a lot slower. If you raise the TA as you have, then you just need to watch out for the pH rising more, though with the SWG turned off and the water being colder it's unlikely for the pH to rise as quickly as it probably did during the summer. If you generally run your TA lower at around 70 ppm in the summer, then you'll probably want your CH a little higher at around 400 ppm unless you keep your pH higher (i.e. not at 7.5 or 7.6). So you can either do what you've been doing or if you want the TA lower you can raise the CH some. Up to you, but what you've got now is fine.

 

[tjslice]

Thanks! I thought I was on the right track, but it is nice to get confirmation. This is my first winter with the pool.