Ok here is my gift to you! If you really want to catch a bunch of flys this is how I do it. I take a 5 gal bucket and put a plastic bag in it. Tape the bag around the top after you fold it over rim to keep the opening as bis and tight to the bucket as possible and so wind cant blow bag around being this is going to be outside. Fill bucked just a little bit covering the complete bottom with fish heads and guts after your fishing trip.( You can use dog pooh in a bind) Place loaded bucket in open sunny area for an hour or more. Have a plastic container that can fit inside the bucket as tight as possible that has a lid ready to go . When ready walk up to bucket quiet with container in one hand and lid in the other. Quickly put the open side of the container part way into the bucket and kick the bucket 1 or 2 times.( make sure you don't touch the stuff in the bottom of the bucket with the container.No need to make a mess!) The flys will always fly up. Raise up the container and place lid on from the bottom as quick as possible. Now to feed take container and get it in the cage from the lowest door and open lid holding container above door opening while opening. Remember flys will always fly up. I caught near a hundred flys in one pass. I would let some get out if you have too many to feed. Remember you could end up with a bucket of maggots in a few days with fish heads. So get rid if it before the end of secound day or else!