Only times ive had my dragon regurgitate, is water, when they have gulped too much while bathing. What veg are you feeding him? Id pop him on tiny tiny little crickets, and lots of them.
I always feed my young beardies (have raised over 300 of them) On small crickets, ive never been a fan of locust/hopper because of there barbed legs.
Don't offer him too much veg (do you have a food processor? blend up all his veg so its small little bits, my young beardies loved it), they should be eating more crickets then anything else at his age, usually about 70% Living food to 30% vegs, this will switch round when he gets older (not a staple rule for all dragons though, some do stick to there live food, my adult male prefers his veg and only eats a few live food).
Whats his water intake like? does he get misted during the day?
Its likely that either his pray was to big, or he has eaten to much. Id stick away from hoppers, there expensive and i just don't like them much lol....
Crickets as a staple diet for a young beared, with some wax worms as treats, never feed them meal worms, and you can change over to Morio worms when they are large enough (16+ months to be sure) there cheap and dragons love them, some adult crickets thrown in now n again will give your dragon something to chase.
what sized hoppers is he eating? (maybe a pic with one next to him to be sure)
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