QuarryShark is just to good!!!
some general tips:
1. Add another clown. They should be kept in pairs to ensure long life.
2. Don't forget those bottom feeders! Watchman Gobys and Sand sifting Gobys, and starfish make wonderful and interesting additions.
3. Avoid preditors. Eels, Lions, groupers, puffers, are awsome fish, but don't make good neighbors. Avoid these fish and you will have a happy community.
4. Tangs are great, just be sure you have the room. 75 gallons can get a bit crowded and may or may not be a good place for a tang.
5. Small angels like flame angels and Coral Beauty angels are awsome, but should be kept only 1 in a tank and should be added last because of their semi-arggressive behavior. also, they have been know to pick at corals so be careful. ( they still make a wonderful "star attraction" so don't be to hessitant.
6. Avoid Damsels at all costs. I was in a pet store and I watched as a group of damsels bassically killed some clowns by nipping off all of their fins.
Here is a list of smaller, realitivly peaceful fish that I would encourage you to look at:
Ocellarius Clown
Yellow Watchman Goby
Firefish
Flame angel
Coral Beauty Angel
flame back angel
Six-Line Wrasse
Chromis
Check out these guys and their close cousins! You will find a large selection of great additions to your tank.