If he's only 4 months old I think he needs more than 10 crickets a day. a dragon that young should be feed 2-3 times a day, as many as he can eat in a 10 minute time. If your dragon only ate one cricket, then something is wrong. Either in your cage setup or the size of the crickets. Crickets should be no larger than the space between your dragons eyes, offered 2-3 times a day, and dusted every other day at that age. Please reply with a discription of your cage setup. Temps, substrate, size, UVB, ect...
Hope i helped

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**Am I the only one that gets frustrated when I cant find just plain old white paper towels?? I dont want any dorky lookin flowers in my snake or dragon cages! Its the little things in life that bother me....**
1.2 Bearded Dragons. Chong, Cheech, Unnamed
0.1 Anery Motley Corn. Cleopatra
1.0 Creamsicle Corn. Faunzy
1.1 Black Labs. Buddy, Booger
1.0 Room mate. Clayton - requires more clean up than my pets.