I catch so many bream that I'm thinking of grinding or cutting up the ones I don't eat, or at least keep the heads and guts and make chum with it out of wheat brand--
That should work. Some of my best catfishing was done with a brim head.
Put any left over parts in your chum bag and just sink/hang it down off the boat.
In a pinch, I've used a couple handfuls of cheap, dry dog food in a sock hanging down.
I keep a turtle trap off the dock here baited with dog food. It's a 3' square of 4" PVC with netting under it.
Carp will also come up and bump it to make the dog food dissolve faster, its sort of their snack bar.