Howdy @Grower New, I run both 5000° K and 2700° K CFL lamps throughout the entire grow (a 50/50 mix of bulbs). On my past grows I used 220 watts total for each reservoir, but this next grow I have up graded the lamps to 480 watts each reservoir and 80 watts of that is UV bulbs. I am hoping that the extra wattage will shorten the grow time (have been averaging 21 to 23 weeks per grow) and the UV to (hopefully increase the terpene production).