Okay, so part of my work is checking a 1200L spa, so I check TA, pH and Br and read a number of the auto-feeder that gives ORP.... So, every day we throw in enough Buffer to kick the TA from 50 to ~100. The next day TA is back around 50. I'm suspecting that the high TA causes the pH to go up and the auto feeder is feeding Muriatic Acid to lower the pH and that is causing the TA to drop.... Am I on the right track here.... It's not in my signature as it's not my pool, I am just part of the team that looks after it...