I do this in my tank, and it's only 30" long. if yours is longer, you'll have an even easier time i'd think... i make sure I always feed my mbuna flake in the right corner of the tank... I get a few sinking shrimp pellets or any other kind of fast sinking food, and while i'm sprinkling the flake in one hand, slowly, so they get a little at a time, i dump 3 or 4 pellets in the left corner of the tank. My syno has learned quickly to work with me... and he knows once the mbuna start feeding that his is coming soon. sure enough, he comes right out of the rocks and gobbles up all the pellets.