JRDroid

I decided to get a 10 watt CFL for my 5 gallon planted build to replace the 15 watt incandescent (inc) that was in it. The difference is staggering. When taking pics of my 5 gallon with the inc bulb in, my camera had to flash to get a decent picture. With the CFL in, it didn't flash and there was almost too much light for a good picture. I was intrigued. So I took the two bulbs over to my ten gallon, which has two spots to put bulbs, so I could compare them side by side. With both bulbs in the middle of the tank (CFL right side inc left side) the CFL's light dominated 9/10ths of th the tank. Only the very far left edge of the tank showed the inc's light color being dominant. Amazed, i decided to take out the 15 watt inc to compare the 10 watt CFL to one of the 25 watt inc's i normally keep in my ten gallons hood. The results were equally stunning. This time the 10 watt CFL dominated 4/5th's of the tank with its light.

To sum up, type of light is more important than watts of the bulb for small tanks (since no one really uses incandescent on large tanks, watts are accurate). Further research (wikipedia) told me that a 9 watt CFL bulb puts out the same amount of light as a 40 watt incandescent.
Pics:
1. 5 gallon with 15 watt incandescent plus camera flash
2. 5 gallon with 10 watt CFL, no flash
3. 10 gallon, 15 watt incandescent on left, 10 watt CFL on right
4. 10 gallon, 25 watt incandescent on left, 10 watt CFL on right

Attached Images

	5 inc.jpg (468.1 KB, 28 views)
	5 cfl.jpg (306.5 KB, 26 views)
	10g 15incV10CFL.jpg (508.0 KB, 25 views)
	10g 25incV10CFL.jpg (396.3 KB, 23 views)

Slug

Its more about the spectrum then the watts in ANY tank. Watts per gallon mean nothing if you have a terrible spectrum above the tank. And a florescent will always be brighter then an incandescent. Your pictures illustrate that well.