With the addition of the clamp on 150 watt MH you should be fine. Just locate the anemone under the light. If you have rockwork that goes up near the bulbs, you can get by with your current lighting scheme. The distance of the anemone from the bulbs is more important than the watts per gallon. A BTA could be fine within say 12 to 15 inches of your current pc system. I would suggest all daylight bulbs to maximize PAR. Also, the age of the bulbs is a factor to consider. Opinions vary, but most agree that you should change the bulbs if over 10 months or so.
If you're considering other species of anemones, Epicystis crucifer is a nice hardy anemone that isn't as light-demanding as the host anemones.