Personally, I would stay away from the dwarves. They stay quite small, and are susceptible to damage from corals and/or filtration equipment. I recommend you to get captive bred, Hippocampus reidi, Hippocampus comes, or Hippocampus barbouri. Two that are too big are H. erectus, and H. ingens. You'll also want a little cooler temperature for some species. The tank may be too small for all of these species in the long run.
