Thanks!

Since bubbling CO2 won't affect TA, using CO2 wouldn't solve my current problem of high TA (which I agree is the main problem with my pH at this point). Nor would it prevent TA rise from my alkaline city water. The only time my pH stayed balanced was when I was using trichlor granular (was cheap at Walmart couple years ago).

CO2 would compensate for the CO2 loss from SWG and, if I'm understanding correctly, from the fountain. I don't know yet how much of a problem they will be, but I am anticipating a problem based on reading some of your other posts. I appreciate the review on using CYA to minimize the SWG operation.

Some of the other methods of reducing CO2 out gassing are new to me. I assume the point of longer pipe runs and/or pointing the returns down is to give the bubbled gasses more opportunity to redisolve. I have about 15-20 feet of pipe to my closest return--but the return is a fountain...

As you say, CO2 systems are not cheap. You may have talked me out of needing one anyway, but what I was wondering was whether I could just get a tank, a regulator and a hose and bubble it myself. A setup designed for beer making looks like it would be about $100. I'm wondering how much acid that would make.

Andy