I'm really surprised that Dutch did not mention CMH (ceramic metal halide) bulbs. These put out alot of UV in comparison to even MH bulbs.

One of the cheapest and easiest ways to add UV is the addition of some reptile bulbs, either CFL or linear flourescents, to your HPS. But as pointed out by Dogsnova on another thread, you may get the same benifits from the use of ceramic incadescents to increase far red, without the health risks associated with UV.
oldmac Reviewed by oldmac on . UVb-UVa I did the best I could to try to understand the threads regarding the topic, but could not assimilate via the written word. Stopped in my local horti- shop yesterday and asked. Interesting theorys. I was/am considering adding another light fixture to my flower room. Would using a MH in one end of the flower area and moving the plants that are closest to finishing under that light improve my yield and trichome content? Currently the flower area is a 1000 W HPS. If you did this what Rating: 5