I was dropping floating food pellets into the aquarium this morning and the oscar shot up and bit my thumb which was about an inch above the water! It didn't hurt; they don't have teeth. I think he was more startled than I was. He shot down to the bottom after that. It felt a little like sandpaper, and he didn't clamp down. It was only for a fraction of a second. I need to buy some long pellets so I can train him(her?) to take the food from my fingers. The stuff I currently have is the size and shape of BB's.