CFL's grow plant very well in the aquarium and out. They will run warmer than fluorescent tubes and should be elevated a bit to protect your top glass from the heat given out by the ballast. Also be aware that you should not hang any electrical bulbs over an unprotected tank. The odds of the light falling into a tank of water is slim, but it's just a precaution.
CFL bulbs have 3 basic ratings energy used, light output and spectrum.
You can find the 3 numbers on the base of the bulb, which is a ballast.
Example: 19/70/6500K
19 is the electricity used.
70 it the amount of light produced
6500 is the spectrum of the light.
The average CFL will be a daylight bulb around 6500k that tries to mimic daylight.
They work well on plants and have had success growing plant indoors using them.
I can even get the plant to flower using the proper photo period.
Just a little more. Plants require different levels of lights.
Using the amount of light the bulb produces you can figure watts
per gallon by dividing the light output by the number of gallons in your aquarium.
The taller the aquarium, the more light you will need to get full coverage to the carpet.
In a 10 gallon tank, 3+ watts per gallon is high light and will reach the gravel at good level of light.
