From Wired Science, Insomniac Cavefish May Hold Clues to Human Sleep Disorders:
To verify that the fish were indeed sleeping, the researchers also explored what happened when they deprived the fish of sleep. They put the fish on top of a Vortex mixer set to its gentlest setting and had it vibrate for 10 seconds out of every minute, all night long. The next day, fish of all four species were far less active.
Scientists fuck with fish; film at 11.