The one I picked up from Karson, actually jumped out of a sealed tank to my feet as I was walking past its tank.
Funny thing is that as I was about to walking back to the females tank to pick one up instead. I went past some tanks that I looked through several times looking for the male melanurus and never found him. For the super male to only jump to my feet. I picked him up and immediately dropped him to the nearest tank. The wife said, I guess he really wants to go home with you, so we watched him for a couple mins to see if he was too stressed out from plopping onto the floor before we bought him.