Well, I don't think there is anything you can do per se, and it may be that they are just not going to eat other fish, and don't see them as food. If you had cichlids it might be a different story. Sounds like they are getting a nice varied diet, so they will not suffer. If you wait a bit longer until you get guppy fry they will probably eat them, since they will be so tiny. Not many fish can resist newly hatched fry. The other option is to remove the guppies and continue like you have been with the bloodworms, flake, etc. I have heard some horror stories about feeder fish purchased from pet stores containing parasites and other diseases, so if you have not done this already, set up a guppy breeding tank so you know the fry are healthy, and feed the fry when they are tiny. Good luck!
