I've had that dream several times. And I know other fishkeepers who have too. I think for aquarists this fish-out-of-water dream is the equivalent of the actor's nightmare dream for actors.
I think the only time I had a seriously fishy dream, was very negative probably why I remenber it the most and I nearly don't want to talk about it... Worse part I can remember all the details and how realist it was.
But it's the kind everything is crumbling, nothing works, they are all dying. You hang yourself with tubing at the end, style of dream.
I prefer when all is good and fishes don't enter my dreams. Loll.