with a 3 tube T5 setup you could get away with your montipora capricornis from mid-high up in the tank. You could TRY an encrusting montipora species, but chances are while it would survive, it would likely turn brown. montipora digitata are pretty much out of the question. As for other SPS, you could try Acroprora Millepora, Pocillipora, and/or Stylophora all up near the top of the tank. Remember with SPS that flow and chemistry are perhaps as important as lighting. And do yourself a favor and dip incoming SPS in an iodine solution to kill any parasitic flatworms or nudibranchs (unless you have wrasses or pseudochromis that will eat them)
