The only thing that is a joke to me is you Chippp. The filter glass does serve a purpose that is why as I stated you must know your
equipment and how it operates you evidently have no idea do you ? Do you have any
equipment with filter glass? Do you know percentages of uva-uvb-uvc in the
lamps? Come on Chippppp I've ask you all day to back up your statements with facts. Can you do that?