Please pardon if I missed this elsewhere on the site (I searched on CO2 and found nothing, and search on "dioxide" got more hits than I could read), but speaking of adding acid--what about adding CO2 directly?

I'm guessing that is what the Pilot product does, and I know Hayward/Goldline has a product that does it--as a +/- $300 add on to a +/- $800 add on to a premium priced SWG. I just saw an automatic unit for about $1300. But I'm wondering if it couldn't be done cheaply with a tank and a hose...

I'm adding a SWG to a pool where city water is alkaline, and I'm running a fountain regularly to keep down high water temperature. We accidentally overfilled the pool a couple times this year, and after 3 gallons of muriatic my TA was 240. (I'm still adding acid...) I'm concerned about my acid bill for the rest of the season.

Is there any reason I can't just bubble CO2 into the pool? Any estimate on how much? Anybody tried it?

Andy