Just saw your response.
Since your beardie is so young, you should dust all the feeders he can eat in about 10 to 15 minutes on one feeding a day for 5 days, then dust with vitamins on one feeding a day for the other 2 days.
At his/her age, it would be a good idea to be sure to offer 2 to 3 feedings of bugs a day. Only 10 crickets a day isn't enough as he needs lots of protein to help him grow rapidly.
Hope that helps.