Don't do nothing but 2700k the growth process is so slow, I had nothing but 2700k 4ft 6bulbs on a T5 ballast 40,000 lumens and had the light cycle on 18/6 for veg, it took 2 months to barely make my plants 12" tall... just fork the money out for both 2700k and 6500k lights.. it's worth it. Plant double to triple in size during flowering stage so if you get them tall during veg stage you'll get more yield.