Since you have only just added the damsels two weeks ago, I would honestly wait to allow the tank time to adjust the bacteria needed to accomidate the recent additions. In a few more weeks if there are no problems (tough wood) then you can look into another possible fish addition. I would recommend you look into setting up the proper >>QT
<< which will prevent introducing parasites or other problems as well.
If the NH3
levels are zero and stable and the NO3
levels are acceptable, you could look into the addition of a good mix of snails to help keep the tank clean.
Keeping the domino's then?