no, once its dialed in (after about a month or so of constant testing/adjusting) you don't need to do anything. When I first got mine I tested every day after making slight adjustments....once I got the bubble rate, drip rate etc set every test was identical and now I test maybe once a month and its always the exact same- rock solid.
I do have a PH monitor, though so I can instantly glance at that when feeding and know that the PH is OK, which means my CA reactor is OK.
I would go with the monitor and screw the controller...JMO