I mix red and blue spectrums in my T5, I noticed a big difference especially in stem growth(stock) as soon as i added 3 red to my 8 bulbs the stock and stems got thicker and seem stronger. I think one of the major advantages of using cfl's for Veg is the ability to give the plants both Spectrums of light which they use in veging. Of course they need more blue, but I'm telling you they eat up some red too....GL