Fred can hardly jump. I was trying to fish out a piece of fur with a q tip once and he leaped at it just before it entered the water. Startled me and I felt him latch on for a second. He tries to jump, but his fins are pretty heavy so he doesn't ever get much air. Maybe a cm or two. Never jumps unless there's something above like a pipette or FOOD. omg when I fed him pellets regularly he would get SO excited(really cute) and start darting around the surface, just about to jump and that scared me xD Especially because sometimes I couldn't manage to get just one pellet. Once, I ended up spilling a bunch of the omega ones because he startled me...not a happy thing to clean up xD THank goodness for vacuum cleaners.
Now he gets an assortment, but he is always always excited to eat. Gets very happy when he sees me...'OH HELLO! FEED ME FEED ME ARE YOU GOING TO FEED ME?!' <3 ^_^
smart little buggers.
I've never been nibbled, and I'm really scared of being nibbled xD I'm afraid i would knock over the entire tank/break one of the walls and it would be a disaster. Thankfully, Fred is a timid little guy and is afraid of things that come at him. (He would be an absolute failure breeder) xD