More light = more lumens = more goodness.

You should be fine.

You prob don't NEED the 400w at the moment. Doing the math, 300w of cfl is roughly 13 bulbs @ 23w a piece. I would wait til they grow some more. That way you shouldn't have to worry about heat when they are that young. Hope that gives you some insight.
Lit Up Reviewed by Lit Up on . Too much light?? I have 7 sprouts ranging from ~1-2inches currently under 300w equavalint cfls (i think they are 23w or something) anywho I also have a 400w hps that im going to use, however can you have too much light for a seedling? I know you can with clones b/c they don't have the established root structure and they lose water, but is this also true for seedlings?? i want to give them the best and brightest 2-3months of their lives, but not over do it. anyone?? Rating: 5