How about a bunch of neon and sharknose gobies? They are cleaner gobies and perform cleaning duties on larger fish.
Scientific names are Gobiosoma oceanops and Gobiosoma evelynae. They are territorial towards each other but then so are clownfish. They do pair up and are known to breed in captivity.
http://www.orafarm.com/otherspecies.html
http://www.reefcorner.com/SpecimenSheets/neon_goby.htm