as far as i know, de bulbs requires uv filter glass, so whether 10kk or 20kk, it is a must to have a uv filter glass not just a tempered glass... tempered glass doesnt necessarily meant it is uv filtering glass.... as for se bulbs, uv rays is minimal, thus most reefers employ the use without any uv filter glass.... but whether its de or se, with or without uv filtering glass, uv rays are still present, its just as to the amount that matters most....
correct me if im wrong....