Thanks Evan. My knowledge of SWGs is limited so I can only provide what I've learned from the SWG users.

I know that pH of 8 is very bad if you don't have an SWG because the chlorine is far less effective, but I didn't know it's even worse if you do have an SWG because it will stop producing chlorine!

I knew that a CYA of 80 is appropriate for an SWG, but not therefore, the correct FC--I would normally recommend an FC of 5-10, and, while it CAN be lower, clearly it can't be more than a PPM lower than the minimun non-SWG pool.

I also knew the lower T/A was better--but, again, not at a level even below the normal minimum.

I DO know that rising pH is very common with SWGs, and that the lower T/A can inhibit that. It's a bit counter-intuitive but it does work.

Again, thanks to Evan for helping me with that.

I just came back from vacation to VERY low pH--it took a full box of Borax and a full box of Washing Soda (soda ash--same as "pH Up!", but cheaper) to get pH back into the safe zone. It wasn't unexpected as I used Tri-Chlor tabs to help maintain my FC while we were away for 2 weeks. CYA isn't very high as the constant rain has washed it out--but with the solar cover one there's been no aeration to reduce the increase in acidity the tri-chlor generates.

Still the water is now fine and warm enough to swim, but the days are getting shorter and the nights are going down to 50 or lower so my solar panels are working VERY hard to keep the water over 80. I'm hoping for a dry, sunny September after a rainy summer so we can stretch the season a little--we haven't swum much this year, and the water only reached 90 once--usually in early August it passes 96 and reaches 98--like a giant hot tub!

Soon, it will be time to close again as another season ends....I'm just not that big a fan of autumn!