Okay, this worked for me. I was able to get a damsel and dottyback out using this method in under 15 minutes.
I purchased a piece of clear plexiglass and cut it down to fit inside my tank from top to bottom and cut a 3-4 " hole in the center of the piece. (you will need a rotary tool to do this) I would then put the plexi in at a 45 degree angle to one of the tank corners.
I would then have a second piece of plex ready to slide in and cover the hole cut in the center.
I used live brime shrimp introduced to the chamber that I created within the tank. Once the fish I wanted to remove entered to feed I blocked his exit with the second piece of plexi, and then netted him.
One thing I found it to be more effective to introduce the food with the tank pumps off. It kept the food from dispersing through the cut out hole.