i have to admit i just buy cichlids i like and then put them in... so far so good... from the picture you can even see dwarf mbuna and demasoni (2-3cm) and they are already in there for a couple of months together with the large Livingstonii and Malawi Eyebiter, Dimidiochromis compressiceps about 6 inches
but the good news is there is a pair or 2 cichlids has been spawning for the past few months.
Realised spawning occurs when the rocks are all placed to the rear of the tank in a straight line so now i placed them all over the tank instead