Buttekoferi, note the spelling it hs two "t" which may help your search for more information. It is a very hardy species, and seems to adapt to most any type of water conditions. I checked out your web site, and see that you are trying to reproduce them with the divider method. I am sure that it will only be a matter of time before you have a successful spawn. It just takes a little bit of time for them to figure it all out.
It appears that you are already providing the proper foods and housing, to spawn this big cichlid from West Africa, just hang in there!!!