Is it ok to be giving wild caught baitfish to my fish? I feel it's better than goldfish. I just don't want to bring a disease into my tank
I would be very careful about your fish self caught minnows, even if you catch your fish in a "clean" place, you always run the risk of parasites. In addition just because source looks clean doesn't mean it necessarily is. Also depending on where you live there may be laws about the transportation of live native fish.
+1
and to add to what Itsadeepbluesea said, make sure you have a quarantine period for those feeders if you really don't want your fish to get sick. If you want your feeders to be more nutitional you could always gut load them with commercial prepared foods.