They are considered algae scrapers in nature, so mostly vegetarian, the waters they come from in Liberia and Sierra Leone are usually considered quite soft, and mineral free, temps very stable in the mid to upper 70s. They were quite popular in the late 80s when I first ran into them as Tilapia joka, and although small, can be very aggressive.
They are found in the same waters as some of the members of the Pelmatochromis genus.