Hi, I'm not sure why no-one else has piped up, but the repti-glo 10.0 seems to be the cause of some serious problems. Are you talking about the tube? To protect the eyes from the low wavelength uvb it should be around 10 inches away, but at that distance the output is quite low. It is the lesser of 2 evils tho, to have it at 6 inches away could give your bd very sore eyes at the very least. The safest way to use it is to have it 10 inches away, and make sure you use a bright white light next to it in order to make the pupils constrict as much as possible.