I keep two fish in the tank, a Rainford's Gobie and a Six Line Wrasse. The only other mobile creatures are an emerald crab, brittle stars, and assorted snails.
The Rainford's is to keep the plants somewhat in check and the Wrasse eats the flat worms and bristle worms. Other than that I don't have much of a want for fish. Oh, I guess I do have a 4 stripe damsel in the 10 gallon below, a friend bought it and decided he hated it a few weeks later and gave it to me. The damsel up until a few days ago had spent most of its life in darkness, not to mention I had around 30 pounds of live rock packed in there for a few months. Ever try packing 30 pounds of lettus and Fugi rock in a ten gallon? I was really quite shocked when every now and then I would see him squirming his way across the front of the tank.