I would have to disagree. As it can work in a few special circumstances, as a general glossy rule it is a bad idea. I say this from experience with larger tanks. 135 and 120. I have done tall and long. I find that my haps and peacocks are in the lower end of the tank. In fact the sand area is where most smaller haps and peacocks are. Peacocks eat by picking in the sand at food they never see. They are all in the same genus because they feed the same. They use pits in their jaws to sense food in the sand. Many haps eat by sifting the sand as well. So I would say that these fish do in fact spent their time in the same areas of mbuna. The other haps are mbuna eaters. So that makes it even more difficult. Now if we are talking peaceful mbuna, well that really narrows which you can have. So as a general rule for most tank, I would say do not mix.
You are on the noise that many see over stocking and take it way too far.
