I have a 75 gallon with an assortment of Malawis and have tried to pick
species so as not to get any cross breeding.
A lfs owner said that if you get species that look too much alike you
will get hybrids, so working from that assumption,
I have:

Red zebras 3
Red top cobalts 3
Acei yellow tail 1
socolofi 3
Yellow lab 4
"maingano" johanni 4
kennyi 3

Your advice is appreciated.

Mark