mine
has started responding very well to earthworms.
Since the day i started feeding him he swims towards me and come to the surface begging for food.
although he can notice when i have entered the room, he sometimes doesn't get where the food has been dropped, keeps snooping around in search of food.
mine doesn't do the play with the food thing, he just comes to the surface and he snaps the moment foods is nearby, i am very careful in regard to getting bitten by him though