"Uh, I guess? It sure looked like the glowing fish from my memories? And 'acquainted' makes it sound like I've talked to it or something. I've never heard or senses a peep from it."

That's taking the position the fish was actually alive in the first place and not just a visual representation of an inexplicable power.

"So... aside from being a ghost... he basically had a boring afterlife? How do you overwork a ghost? Why would ghosts need to work?"