You typically won't see those large rubbery lips in captive bred fish.
I've posted the following a few times over the years whenever someone attempts this. In the wild, those thick lips serve as gaskets, and are used to extract prey from the cracks and crevices in the rock piles where they feed. You'll see the same thing with some of the fish found in the Rift Lakes, such as Placidochromis milomo. IMO using gel food, lava rock, etc will not net the same results in captivity. It has also been speculated (by Konings and another author that slips my mind at the moment) that in the wild those large lips carry numerous scent sensory pores, which are utilized to seek out prey in the cracks and crevices of the rocks. Again, a characteristic that is most likely lost on domestic fish.
In the wild, the feeding behaviour of the fish will determine some of the physical characteristics of the fish, such as body shape, head shape, jaw size, lip size, and even size of the eyes. Again, this isn't going to be duplicated by simply putting some lava rock in ones tank.