I live in an area where my fill water has moderately high TA and high pH. (Often has pH of 7.8 to 8.0.) Also the dirt is highly alkiline, making another way for the TA to rise. I generally don't have the TA in the recommended 90-120 range. Generally when I measure the TA it runs about 130 to 160. I haven't had any problems with "runaway pH" so just put in acid when the pH gets to 7.8 or above. This morning, however, when I tested TA it was about 100. 
Guess just putting in acid every so often to keep the pH in check also put the TA down to recommended levels! (Wonder if that means my pH will be even better at staying down? I generally put in about a cup of acid a week or so.)
Guess just putting in acid every so often to keep the pH in check also put the TA down to recommended levels! (Wonder if that means my pH will be even better at staying down? I generally put in about a cup of acid a week or so.)
:-D
