proper name is Dimidiochromis comprecisseps.
they prey on small fish/fish fry in the wild, and they are incredibly adept at doing it in the aquarium too, although while only 3-4" long the only fish they can really eat are small guppies.
carnivorous/protein pellets are a fine primary diet for them.
Both sexes start out silver w/ black stripes, but the female stays that color while the male develops a striking blue/turqoise color throughout its body as it matures. Male gets like 10", females 7"
They are not good tankmates with mbuna, as mbuna tend to bully them too much and are excessively active.
They are territorial toward other african hap species.
They are best kept in a fairly placid, tranquil tank without too much tankmate movement.