I don't know if this has been mentioned, but UVC, or germicidal lights are not good for your plants.
Excerpt from here
http://www.cannabisculture.com/v2/articles/4715.html
UV Shield I?m growing a single plant in a closet using a 175-watt metal halide lamp. The lamp itself has a glass cover that says UV shield. I?ve read that the more UV radiation a plant gets the more THC it produces. Should I remove the cover from the lamp? Should I use a germicidal lamp?
Mike M.
Rock Springs, Wyoming
No. The lamp emits UV-A and UV-B light, which increases the potency of the bud, but it also emits UV-C light, which is fatal to life forms. Do not mess with the lamp. If you wish to increase the amount of UV light the plants receive, use tanning lamps or fluorescent lamps designed for maintaining reptiles.
The tanning lamps emit copious quantities of UVB light, which promotes tanning, and the reptile lights emit an enhanced quantity of UV-B light to maintain reptile health.
Germicidal lamps should not be used to illuminate gardens because they emit large quantities of germicidal, but carcinogenic and otherwise dangerous to humans, UV-C light. In order to filter out the UV-C light and let the UV-B and UV-A pass through, the fluorescent tube would have to be wrapped in a cellulose acetate film shield.