can you buy ice?, yeah it seems like a pain if you have to go through all that trouble. can the flies completely fly?if you're just trying to move the flies from their holding container to the mantid's container, a metod a friend of mine devised works really well.if the flies are in a deli cup. take a second lid that will snap on the cup, cut the center from it, and glue a funnel to the top( so the funnel is pointing up, out of the cup, you can use paper for this. then, cut a hole in the mantid's cup, that can be plugged with foam or cotton, Like Rick does. and when you need to feed the mantis, tap the ff cup, change to the funnel lid, put the funnel tip into the hole you cut in the mantid's cup and let the ff's walk/fly up into their "death chamber"tap the ff's cup again replace the solid lid , and plug the hole in the mantid cup. done. ff's will usually walk straight up, right up where you want them. hope that helps.