I have found from my years of self research. That mixed spectrums seem to grow better yeild . If all other factors are in order. Speaking of mostly autoflower experience. Therefore the success of constistantly producing large autoflower yeilds, Due to obsession . Has found that , yes light is a very important factor concerning yeild . Anyway My personal belief is that blue spectrum promotes new growth and red spectrum promote flowering. So i always use MH for first 2 weeks then both . At a 1/3 MH- 2/3 hps of total watts used . throughout remainder of grow. Guess that is why them led and other mixed spectrums do well. Just thought if you could promote growth while flowering, the yeild would improve. not sure , but it hasnt hurt anything:thumbsup: