Phoenix worms are a great feeder for young dragons. Just feed them when they are still very pale in color. Once they turn dark, they are not as nutritious. (the calcium converts into the hard exoskeleton when it pupates..not as easily digested at that point).
Other insects that are good for young dragons would be butter worms. Some may be too big for very young dragons but often batches are mixed...and even the really big butterworms are not that big, an inch long or a little more. Most tend to be around half an inch but quite chubby. Butterworms are more costly but can be stored in the fridge.
Hornworms (only farmed ones, not wild caught ones, as in the wild, hornworms eat tobacco or tomato plants which contain toxins that can be deadly to your dragon. When farmed, they are fed a special chow that does not contain these toxins.) get rather big (also called Goliath worms) and grow very fast so are not really the best feeder worm for young dragons. Once your dragon is over 14" then feeding them hornworms for variety is great. Hornworms can grow up to 4"-5" long. (silks tend to be 2-3" long).
The Can O' series can be used too..just make sure you buy small cricket size. But keep in mind that some dragons won't eat 'dead' prey so it may be difficult to get your baby eating it. Sometimes just dropping the canned crickets one at a time gives enough 'movement'.
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PHLdyPayne