never use mealworms myself, not a very good feeder insect for bearded dragons. I do use superworms though. I don't find it hard to separate the worms (even mealworms, when I used to get some for a smaller lizard I used to have) for feeding. I just sift them in my hands to remove the bulk of their bedding/poo.
To help prevent any dust stirred up from sifting through worm bins aggravating your ashma...pick up some dust masks you can get at any hardware/home improvement or even dollar store. These masks are designed to prevent very fine particles from being inhaled (ie plaster dust), it should have no problem blocking worm poop and dust from being inhaled.
I have developed what I believe to be dust allergies...so I use those masks when I sweep, dust etc...or expect to stir up any amount of dust..to help keep from going through a bought of allergy symptoms...as I don't like taking pills all the time if I can get away with it.
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PHLdyPayne
Forum Princess