Mbuna species are regarded as an herbivore. I won some at a fish auction and placed them in a planted tank. I assumed they would devour the plants. They did not eat them. The algae was not even eaten. In fact, mollies do a better job at eating algae then the mbuna. Since I've had them, the mbuna have been fed beef heart flakes. I keep them in a planted 30 gallon high with fine sand. When they first went in the tank they would swim around. Then, they just dug holes and created territories. It's cute to watch them dig the hole. The mbuna will use their bodies and mouth to make the hole. Now they lay in their holes and wait for the beefheart flakes. They are growing fast. The species is Pseudotrophus acei (ngara).