A general answer: wrasses, cardinals, basslets, damsels/clowns/chromis (all the same general family), dartfish, dottybacks, some gobies.
For a more detailed response, we'll need tank size & what corals you plan to keep in your reef (as mentioned above).
You can go look at liveaquaria.com and browse through the fish there, each has general details on what/where it eats and hangs out in the water column. It also gives good guidelines on appropriate tank size and aggression.