Again, thanks. I better go buy that other 10.8 pound bag of baking soda, looks like I might need it based on the test results, your reply and the Pool Math calculator. Feels like it’s getting close..Yep, you are correct. Wow. Okay, starting adding baking soda. For now, add about 40 ppm as noted above and test again in about 30-60 min. You need to get the TA to at least 50 and the pH "should" start to respond and come back up to the 7.2 range. If after getting the TA to 50 the pH doesn't respond, you can increase the TA to 60, then 70 if needed.