Question on the 'sanitizing' aspect...
This was a sudden onset thing. One trip, it was fine. Next trip, few weeks later, nasty smell/taste.
Only major changes were a) the new hose (used one time) and b) the new anode (in the tank for every flush and refill).
How likely is it that the entire fresh water system got contaminated by that hose, that one time, to this extent?
We're definitely going to do the bleach sanitizing routine; sounds like we should have been doing that all along. Live and learn.
Probably borrowing trouble here, until we see if that works or not, but I'm a little skeptical that we picked up some sort of bacterial problem that fast unless there is something else at play here.