Well, IMO plants do best under a higher spectrum tube. The bulk of the lighting on Phoenix44's tank are 4xT5HO PowerGlos (18,000K), and Jennifer uses these on her tank as well, and surely you've seen how well the plants are doing? :-?
I wouldn't bother growing plants with any lighting that's under 6,500K.
What tubes did you get? The sunlight ones, the tropical ones or a combo of both?