As far as how many fish i cant say unless you decide on a type of african cichlid. Their sizes aggression and needs can be vastly different.
There are the 3 rift lakes. Malawi, Victoria, and Tanganyika. Then there are the rivers and some west african cichlids and some of these are from softer water. The 3 rift lakes are all hard water with lake Tanganyika being the hardest water. You dont want to mix and match your stock from these different bodies of water(for the most part unless you are sure of what you're doing!).
Now when shopping for them you'll mostly be seing Haps, mbuna, or peacocks ( there are others but i'm tryn to simplify) . Most Haps and peacocks would be stressed out by mbuna... So again try not to mix these either.
For substrate you will want to use sand and larger rock( for the most part). Thats really about it for decorating. You can make cave like structures with rock for thm but make sure its secure. Many of these fish love decorating on their own so they often dig or push rocks around.
You should shoot for a turnover rate of 10x your tank volume an hr for filtration or close to that.
Make sure you research each individual fish to make sure they don't get too big, hei diet is similar to the others you keep, they are fron the same group(Hap, peacock, mbuba etc.), and same body of water or at least similar.
For "cleaners".. Well there are some kinds of catfish that will work personally i have an African featherfin with my Africans and he does well. But keep in mind if you get anything for cleaning in there its not really going to clean exactly. In fact many of these cichlids themselves kinda could fit into that category. For example many mbuna love algae and spend lts of time on he bottom.
Last edited by Agent13; 11-26-2013 at 12:08 PM..