@sleezy - Ideally I try to keep it an even distance away, but one of these ladies feels like stretching for the stars and is literally 3 inches away from the light and showing no sign of stress.
@Blackmesa - Thanks and thank you for the link too! Ill definitely check it out. I would definitely recommend the 500w Blackstar. The plants on either side where the UFO light was the primary light source lacked in size and flowering so far compared to the 500w, so I pulled them out and am not using only the 500w.