My BGK about 9 inchs now - almost a year old in a 72 gal bowfront.
He eats frozen bloodworm - his fav, other assorted frozen cubes like beef heart, flake food, and he really loves the sinking wafers I try to give to my Cory's.
He just discovered them recently and it is fun to watch the race/chase between him and the 4 Cory cats. He has shown zero aggression towards any of the other fish in the tank, but he is like a steamroller when it comes to feeding time....he doesn't bite, he just rolls on through - in true BGK fashion - usually backwards.