I'm no help on CNBG growth, but I keep a few BG females in a holding pen and hand feed AM500 to them. It's one way I try to manage my spawn rates. Every female I catch goes in there. Probably not near as many individuals as you're thinking, but the few I have seem to be doing fine. I'll let them grow until they get big enough to dance with some hot grease.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!