running the swg in cooler weather in spring?

Apr 22, 2011
Hi all again, back from a mild winter up here in the semi-frozen north. This is our first pool opening ever.

We opened the pool opened last week to crystal clear water. :party: Fella who opened the pool said I should not turn the swg on until the pool water hits 65 degrees. It hit 78 degrees earlier this week, but with all this rain and much cooler weather, it's dropped considerably.

Why is it that I need to wait until 65 degrees? Should we be running the filter to keep things moving? I checked my cya and it's 50 but can't even register the FC. Turned on the swg for a day, but then turned it off because the temp dropped.

We have an agp that gets 100% sun all day (when it's not torrentially raining that is).



TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
It varies somewhat by brand, but most SWGs are good down to around 55 or 60. Below that some shutdown, while others simply slow down their production of chlorine.

If the SWG is not producing the chlorine you need, you should be adding chlorine manually. You never want the FC level going below the minimum for your CYA level.