yes and no.. hows that for a answer
Seriously though actinic light VHO of the same intensity as say a 10000K VHO would actualy be more usefull than the 10000K, the problem is the actinic light (in the same type of bulb) is usaly less intence than a Day light bulb.
Having said that deep water corals have adapted to be able to more efficiently use the lower nm light spectrums (ie actinic and blue light) so in some cases it is just as good.
now weather you can count the wattage to figure out how much light you have I will have to say no.. you can't count the wattage of any type of light to say how much light you have going into your tank. the reason I say this is wattage is only a measure of how much power the bulb consumes not a measure of how much light it produces, so you would be better off using intensity or PAR as a measure of your light. The problem with this is light meters can get expensive and not many stores will allow you to measure a bulb befor you buy it.
now having said all that I will through one more twist at ya.. instead of saying watts/gal which can be totaly messed up by how deep a tank is, how about saying watts/square foot of tank surface. this will more indacate a measurment of how much your light is spread to cover your tank. still not a accurate measurment but it is a lot better than watts/gal.
Steve
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