I have never seen BG that wouldn't train to feed in the pond on appropriately sized pellets-eventually..
But, with that aside, nothing wrong with trapping some YOY or buying some and working with them in the aquarium.
I'm guessing some sinking or hydrated feed to start with would be best. Starting with small pieces of worm and slowly adding a few pellets. Others here are masters of feed training so I'm not going to pretend I am, but I did successfully train my first 2 big batches of perch this year by instruction of Bill Cody.
Have fun with it.
