i agree with harry wholeheartedly. moreover, this is a fish that takes a commitment on your part. frontosa are maternal mouth brooders and do best in groups of 6-8 females and only ONE male ... and that in itself dictates a tank of at least 120 gallons. less than that number and you can expect alot of fighting, torn fins and scales, disease and ultimately death of some of them.
when juveniles, you 'can' keep them with other cichlids such as those from Malawi .. but when they reach sexual maturity at about 3 years, you had better remove ALL other fish from their tank.
remember ... be a responsible hobbyist and don't cross breed the various forms from different collection sites. i.e, don't mix 6 stripe with 7 stripe etc.