Here's what I've done in the past with a stubborn bass. Cut a piece of shrimp into the general size and shape of a feeder fish. Take a 2 foot piece of fishing line and tie a knot on one end, now thread the piece of shrimp onto the line until it stops at the knot. Drag the shrimp through the water and when the bass grabs it a quick tug on the line pulls the knot through. You may have to adjust the size of the knot, to big and it won't pull through and to small and the shrimp falls off. Don't feed then for a few days and give this a shot, I haven't had to do this more than a couple days after the bass take it the first time.
Good luck.