the only thing i buy in bulk is plants... use what i want and sell the rest to the lfs... but i feed my cichlids cooked steak.... and i live on a farm.... so i'm good there....
You might want to STOP doing this. I have seen in a few posts that you are having trouble keeping fish alive, and this could well be the reason. Beef is high in mammal fat and fish don't do so well with it. Also, the tank water doesn't appreciate it much, either.
I always buy the bigger bottle/bag when I am in need of something. 9x out of 10 it is cheaper to buy the larger amounts. I buy large bottle of discus buffer, aq. salt, food, etc. Costs more per order but less orders mean less shipping costs too.