I personally wouldn't do it as the change of lighting may cause your anemones to move, and they are already in ideal spots looking at the picture.
...How do I acclimate? ...
I went from 6x54 watt T5 fixture(324 WATTS) to a 2x250 +4x54 actenics(716 WATTS) my electric bill is only about $10 to $15 higher.Imo I wouldn't change lights,your anemones look great.