No you do not need Metal Halides or Actinic bulbs. If all you want are fish you really don't need any light. Personally I like using a twin fluorescent strip light with a 10000K daylight bulb, and an actinic light (really makes the fish look nice).
Sam Reef
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90 Gallon FOWLR Marine system
20 Gallon Reef
10 Gallon Reef
20 Gallon Planted tank