Yeah, CFL's aren't going to be effective lighting on a tank that deep. To have anywhere near a decent planted tank, you'll have to do Power Compacts or Metal Halides.
Yes, the wpg rule doesn't apply, but putting 100 watts over a 600g tank tank that's 30" deep isn't going to grow plants. For a high tech 600g tank, you should shoot for about 430 watts. Low tech, *maybe* half that.
But, you might could use a couple of these babies:
http://www.1000bulbs.com/105-Watt-Compact-Fluorescent/31681/
430 watts isn't even 1 wpg how's that high tech?
430 watts isn't even 1 wpg how's that high tech?
Because with big tanks like that the watts per gallon "rule" doesn't even apply. It's not even something you can work with. For a 600g tank, throw the wpg rule out the window.
Supporting information:
http://www.aquatic-eden.com/2006/11/amanos-ideal-light-levels-revealed.html
and
http://www.fitchfamily.com/lighting.html
Its not really supporting information. for it to be supportive wouldn't it have to be in a controled enviroment and multiple test run using the same exact parameters..... Just my opinion
Well... From looking at Amano's tanks and if the data they gathered is from his tanks and accurate as they claim about what wattage he uses on all his tanks of different sizes It might be good support. Its hard to argue anything against an Amano planted tank. according to the calculator I'd need 430 W