Shellies have a HUGE personality for such a small fish... My Brevis got pissed off when I moved shells around... They got pissed of to the point to actually trying to bite me... They weren't breeding or anything... Definitely a great fish... Good Luck!
You should definitely look into getting Synodontis Lucipinnis... Tiny little catfish same size as a shell dweller... Have just as much personality as them too!