Having metal halides over the tank is great, but it would help to know the wattage too
, I would wait awhile before you get an anemone. They really do much better (have a better chance of survival) if the tank is mature, and the aquarist experienced. Give yourself and the tank 6 months and you should be ready. This will give you more time for research anyway!
When you do get an anemone, I would recommend that you get a captive bred one which is usually the bulb tip anemone (BTA). BTA's tend to do better than any other hosting anemone but be warned that even the BTA may outgrow your tank.
If you are not concerned with a hosting anemone then I would say that a flower anemone is the way to go. They stay small, so it won't ever outgrow your tank and they aren't being threatened in the wild.