Mark, it's not only about pounds of forage for the LMB, it's about the size of the forage. Bigger LMB won't put on weight chasing down a bunch of small fish, they really need fish about 1/4 their body length, and plenty of them.

Keep a log like Travis said, but initially, it sounds like the smaller LMB are eating a LOT of the forage that should be growing bigger to provide forage for the larger LMB.

The log will tell us the picture in greater detail, but I'd bet that you will end up culling a lot of the smaller LMB too, even tho they are fat (to let some of that forage grow to support larger LMB).

Keep in mine 10# of forage (of the correct size) puts 1 pound of fish flesh on one LMB.

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).