I know that they would use the same amount of energy to power so they would have to be equal (right?) but, is there any difference in their respective wavelengths?
This problem arose from trying to light up a fish tank with enough intensity to sustain delicate sea anemones!
Would both instances penetrate the water to the same depth?
I just replaced a light fixture in my kitchen which used two 60 W incandescent bulbs with a new one using two 18 W fluorescent bulbs. The new one gives off as much, or more, light than the old one, but uses less power.
Since fluorescent bulbs use a completely different technology to create illumination, there are differences not only in the amount of light produced, but also in the color temperature (or wavelength). Flurorescent bulbs give off a whiter light than incandescents, which are more yellow in color.