The first couple of batches of crickets I bought lasted for a few weeks until they were all eaten. Then I bought 500 small crickets and within 5 days they were all dead. I thought it was just a fluke so I ran to the petstore and bought 5 dozen more....and within 3 days those were all dead as well. What's going on?? I need to order more but I'm scared to now because I don't want them to keep dying.

They are are kept in a large critter keeper with egg crate. Room temp at about 73-75 degrees. They are fed fruit and veggie baby food. Would sprinkling the calcium/vit D powder on them kill them? The 5 dozen were in a plastic bag and I sprinkled powder on them and fed some to the frogs and dumped the rest in the container.