Based on my experience, I wouldn't do it if you are thinking about a breeding pair.
I put a couple in a uk 55 gallon Mbuna tank. They are not big, and look nice, what harm could there be? I had a chunk of tufa rock in the middle of the tank which they took over for egg laying purposes.
When the eggs hatched, they made three quarters of the tank their territory, herding much bigger fish into one corner, - fish which were up to five- six times bigger!
I once watched horrified as the male took a chunk out of my prize demasoni's dorsal. I bought a bigger tank, they just made their territory bigger.
No messing about with mbuna's "nose to nose aggression dancing" or playing tag around the tank, they just go and bite.
I've read that it gets worse, the babies join in on defending the family territory once they are big enough.
Lovely fish, but they had to go.
