We had talked about HBG and regular BG, so maybe it was just BG he said to do 500 of. I looked and here is what there website says:

IF YOU DO NOT PLAN TO FEED YOUR FISH A COMMERCIAL FISH FOOD:
COMBINATION OF: Channel Catfish-400/acre
Large Mouth Bass-200/acre
Bluegill/Hybrid Bluegill-500/acre
White Amur/Grass Carp-10/acre

COMBINATION OF: Large Mouth Bass-250/acre
Bluegill/Hybrid Bluegill-500/acre
White Amur/Grass Carp-10/acre

HYBRID BLUEGILL:
(ONLY) Hybrid Bluegill-750/acre
White Amur/Grass Carp-10/acre

CHANNEL CATFISH:
(ONLY) Channel Catfish-400/acre
White Amur/Grass Carp-10/acre