Those, the Azure & Yellow-tails were my first choice. Very beautiful, mellow (for damsels anyway) fish. My Yellow-tail was the least aggressive fish in my 36 gallon tank until after the heater malfunction. He then thought he owned the place. a fatal error as the fish added afterwards were more than capable of defending themselves. R.I.P little guy..
They are also extremely hardy it & my ocellaris survived that awful disaster with no ill effects.
But in a smaller tank, you may not be able to keep more than one, without some serious aggression occuring between the damsels.
Sincerely,
Matthew