Please don't laugh at me! If you wan't something interesting try a sargassum, bluejaw or crosshatch trigger. I have had a sargassum for 6 months and a bluejaw for almost two years with clams, SPS corals, snails, cleaner shrimp, etc.
They have been 10 times better than any tang, clown fish, dwarf angel, etc that I have had. They don't pick on the shells(like my chevron) kick up sand (like everybodys maroon clowns). Nigers and Pinktails are too big of a risk. IMO these are the only 3 triggers that are safe in a reef with clams.
I know some others that have kept bluejaws in a reef and have never heard negative stories unlike the Nigers...