Week 6:
Onions are fine, the peppers, so-so; the melons and cucumbers, meh. Given the steady decline in health I'm doing the only thing I can, greatly increasing the time between fill cycles, going from 5 times an hour to once a day. Been running it that way for almost a week and it's kinda funny in a sad sort of way that it doesn't seem to matter. While they don't look any worse, they don't look much better either. Not much else to do than let it run its course. The peppers have formed but who knows if they'll grow to maturity.
Overall I'm not real impressed. Next spring I'll give it another go, planting everything when it would normally go into the soil. As it is, we're moving into Fall so I don't know if that's part of the reason for the less-than-perky plants.
This is partly why I ran this test; I became suspicious how YouTube videos concentrate so much on the building of the system, yet we never seem to see videos of the bountiful harvests. I suspect the dream may be better than the execution, but I'll give it another try next spring.