Depending on tank size specifically depth. Arguably all anemones need very high lighting, VHO, T-5's or MH. There are arguments to the contrary on some species. IMO there isnt enough proof out there that shows less is better or as good. And in most cases these animals do better with higher lighting. But thats just MO. Watts per gal is not an accurate way to determine if your anemone has sufficient lighting. A hypothetical example would be, in a tank 24" high 100 watts of PC lighting would not be enough to keep an anemone happy. Although 100 watts of T-5 lighting most likely would, t-5's have more lumens per watt output making them more intense. Squashing the theory of watts per gal. Unfortunatly there is no way other than a lumens meter or a PAR meter to determine how much more intense they are. But intensity of the bulbs is key not watts.