I don't know much about the particulars of superworms but I use them to add variety to my bearded dragons & monitors diets.
I'm sure they're age at the time we get 'em is a factor but I ordered either 500 or 1,000 2 - 3 months ago, or maybe even longer, and put 'em in a 58-quart Sterlite container with a mixture of chicken scratch, laying mash (for chickens), and oatmeal bedding and an egg carton. I've still got some left. I'd venture to say that less than 30 have died (not 30%, 30-count).
The only ones that have pupated are a few that escaped one of my monitor's feeding bowl and pupated in the aspen bedding. The monitor usually beats me to 'em.
I'll be ordering more soon and will probably try my hand in raising 'em.
Have a good one!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American