That makes sense, Jim. However, in the past, I just change the media and all is well. In this case, I did a serious breakdown and cleaned out quite a few orifices in the check valves, bubble counter, etc... and with the pH controller in charge, I didn't expect such a change.
Also, something surprising happened to the built-in bubble counter on the reactor. I never use it, but the tubing connects to each end. It's been like this for years. When I cleaned the reactor recently, I removed the bubble counter and noticed some cracks in the acrylic tubing. Age-related, I'd assume. Anyway, I came back from my trip, and it has 50+ cracks in it, both vertically and horizontally. Absolutely nuts. I took it out of the equation for now, and will post a picture later.
Sorry to hear about your rain, and the need to pump out your basement. That sounds like unpleasant work. Did you have anything down there that was ruined?