I would think that flies would get freezer burnt. And all the vitamins and moisture get kinda sucked out. Maybe if u could find a way they wouldn't get icy. Canned crix are a good substitute for live foods. Some members don't like them. But I called exoterra today to get details on processed crix. They are put in cans alive, I thaught they smelled salty and was concerned. I'm also afraid of using mealworms because of impaction. Good to hear you're not having problems that way. as far as bloodworms, I would use internal search and see what comes up. I know earthworms are a balanced meal. But those are hard to find in winter and baitshop suppliers have theirs hibernating. Good to have u on forum. Hope to hear more