does this light even do anything?

[Hans]

i have a 5 watt inc bulb on my 2 gallon reef. wondering if i could have any type of coral because, techincally its enuf wattage per gallon right?

 

[mogurnda]

5W incandescent is equivalent to about 2W fluorescent. Also, the smaller the tank, the higher the ratio goes. I have 13 watts PC over my 2 gallon refugium, which is good for macroalgae, but and maybe for easy corals.