I am so frustrated. I decided to do a partial drain and refill to reduce my CH a little this year. I got it down to 530. I don't really know how high I started because what I thought was 580 was a low reading because of how I was doing the test. I now use a magnetic stirrer and get much more consistent results. After I did the partial drain, my TA was high (170), which was to be expected since the fill water tested at 210. I have been working on lowering TA and got it down to 110 right now, although the ph is still 7.2.
The problem is, my CH is now slowly creeping up again. I am thinking that the ph reduction involved in the TA reducing method we use might be causing some corrosion to my plaster. This is a big bummer if so. We have had no rain or leaking or anything causing a huge use of fill water (highish CH).
By trying to "fix" things, I seem to have opened a whole new can of worms.
Anyone care to weigh in? I might not respond quickly because I will be out of town for a few days, but let me know your thoughts anyway.