Here are a few fish that I have really liked over the years. Most of them are small, and easy to keep.
Spotted hawk or Pixie Hawk - Lots of personality, will eat shrimp etc.
Royal Grama - Just about the perfect reef fish.
Marine Beta - another good reef fish.
Dwarf angels - With caution, some will eat or annoy corals. Sometimes depends on the individual.
Most gobies - nice fish, but often hides, you'll need to look for them in the tank.
Pajama cardinals and Banggai Cardinas - also good choices. They look good in a group.
Clownfish - Another popular fish. Make sure whatever you get here is healthy and disease free. Can be aggressive.
Fish to add with caution or not at all -
Dottybacks - lovely to look at, very aggressive, add it as the last fish
Damsels - again lovely, but aggressive, avoid most species unless you want an all damsel tank.
Tangs - avoid unless you get a much larger tank
Jawfish - fun to watch, but need a deep sand bed
