Another old-timer here that became handicapped several years ago. Started growing for something to do. Plus it helps a lot with the pain. Went DWC with 8 buckets inside a 4x8 tent. Decided to go hydro because it is out on my deck and didn't want to deal with dirt. Had my share of fits & starts. Just put crop #7 in the buckets yesterday. Lost many plants to root rot - would get them to just start to flower then pffft - gone overnight. After pinning down the problem. I have switched over to inorganic nutes - organics will FEED ROOT ROT. I have one plant from my last grow that managed to escape root rot. I now use a fungicide weekly with it and the roots look marvelous. I took the other 7 buckets and completely bleached them - including clay pebbles. I have upgraded from a cheap round like a ball air stones to 6inch diameter air diffusers in the bottom of the buckets. Upgrading my air pump next to keep up with them - my original pump isn't really strong enough. The 7 buckets were air-dried for 3 weeks between being sanitized and being put back to work this past week when I got them arranged on one side with air on and water in them. I also dosed them with fungicide as a preventative. Planted seedlings started in rock wool cubes in the baskets with the clay stones yesterday and got the light on the timer - 18on/6off with the light on the low setting. I grow all Autoflowers and get 3 crops/year. I shut down and drain and air-dry the system in winter for 12-14 weeks.
Not a lot in common with your setup since you use the reirc DWC method. But if you want to chat feel free