I do not have brave fish. I have two monstrous fish with vivid imaginations. They get spooked by imagined threats, and it takes crashing into a tank lid or wall to bring them back to reality. Leonardo managed to slice off his lower lip. Thankfully, his lip regenerated.
Last month Adonis managed to fillet himself open with 2"+ very deep open wound behind his head. It was too hideous and gruesome to take a picture of. I am glad that it is healing well.
Both injuries were so terrible, I feared for their lives. (I'm sure if a smaller fish had similar injuries, the fish would not survive) They are so big and powerful, they can hurt themselves really badly launching into tank lids. I wish they were brave and didn't spook, but then they wouldn't be the lovable gentle jolly giants that they are.