I think they do breech to gulp air.. maybe? I know I leave my tank water 2-3" from the top area because my Del breeches to breathe and I could see that ending badly is she hit the top to hard or did it by the filters and flew out lol
I think I will just bury the guy. Its really annoying because his little brother/sister who never ate as much as him, hasnt really been eating since big guy jumped.