As many as he will eat in 15 minutes 2-3x a day. That can be more than 50 per feeding, but every dragon is different, and every feeding can be different depending on if he's shedding or having a growth spurt or just feeling hungrier that day. They will not overeat, so however many he eats is how many he needs that day. You should always err on the side of buying to many for him to begin with, so assume he's going to want 50 (that are smaller than the space between his eyes) at every single feeding.