The man is full of nonsense. You can get the same effect by simply using an unshielded HQI metal halide lamp or LEDs.

Also, UVA isn't really the best UV wavelength to use. UVB is what you want.
khyberkitsune Reviewed by khyberkitsune on . Black Light Usage I just finished reading The Hydroponic Bible by Chris Kovach. In the lighting section of his book he states that using a black light 3 times a day in 10 min intervels cause the trichromes to just grow like crazy. I know that using a black light to grow with is a death sentance to the plants but apparently not at these intervels. Has anyone here ever heard this or tried this method before. Thanks everyone Rating: 5