OK - noob here, trying my best to get my spa in order.
first, the setup:
850 gal in ground pebble spa with waterfall
Chlorine from SWG
Water is usually kept at whatever temp then sun makes it (73-80 this month); We'll bump it up to 90 to use it (the kids don't like it much hotter than that) and currently we're only using it about once a week.
Now the problems:
TA = 70; pH = 7.8, CH = 320
I've had the TA up to 90, but have been unable to lower the pH. As I try to lower the pH, all it does is reduce the TA, so now it's back to 70 with only minimal reduction in pH. I'm going to add baking soda to bring the TA up, but my fear is that this is going to raise the pH again. At first I thought pH is not coming down b/c I've been using some older muriatic acid (years old from my parent's pool) but it's been stored indoors, sealed; I read that MA doesn't really "expire"; plus the TA is coming down, so I assume it's working. And it burns if I accidentally get a whiff of it
As an aside, I'm also trying to lower my chlorine a bit - my SWG was set at 80% (running only when the fliter runs (from 0900 - 1700)). Chlorine has been running around 7 ppm. I've now reduced the SWG to 55% and really no difference in chlorine reduction. I did turn off the SWG for a day and my chlroine when to zero. Now that air temps have dropped from 95 to 70, I realize Cl is not being used as much, but any tips in getting the Cl down to 3 range (just keep reducing the % it's running???). I haven't tested CYA yet - getting ready to do that today.
Thanks for your help. This seems like a great forum.....