the only cichlids i know about are from lake malawi , i have two 55 gallon tanks, i do 25% water changes every week.and i use aquasafe. i have two 350 penguins on each tank. filtration is very important, cause contrary to other fish you have to crowd a cichlid tank to keep down agression or use target fish which i don't.
where i live the water is hard so my ph stays around 8 which my fish love. i haven't had not one die in 5 yrs.
it's also good to make sure all your fish come from the same lake so they will be compatible. in most pet stores the writing just says african cichlids that could mean any lake in africa... and most people who work there don't know anything about fish. your best bet would be to look in the fish forums on all the fish related websites the most helpful one for me was cichlids.com.. hope this helps