They are one of the fastest growing cichlids there are. In 5 months, my 3" Emperor/Chocolate cichlid went from 3" to 9" and got really wide. Very docile fish with a great personality. Generally known as a gentle giant with little aggression issues. Prefers to eat bugs (crickets, bloodworms, flightless flies, etc.) and vegetables (peas, spinach, lettuce, cucumber). High quality cichlid pellets and tabs containing spirulina are also encouraged. They spend 90% of their time at the water's surface searching for bugs. Minimum tank size for a single Emperor should be 90 gallons. The fish also has a large bio load, producing a lot of poop. Price varies but should not be too expensive. I paid $50 usd for mine (at 3") which was a well bred fish, they also had wholesale emperors for half that price as well but I opted for the better bred/looking fish.
What size tank are you planning on for him, and are you planning on any tankmates?