As most know I'm out of touch with many of the new fangled herp equipment out there UVB bulbs where still just being talked about when I got out of herps for a while. I've been reading what I can as I find it and was inspired to rething things after reading the post linked below... http://www.herpcenter.com/habitat-lighting/42085-uvb-results-compared-through-screening.html As to not clutter up that thread I started a new one. But much of what I have to ask is kind of connected with those findings, so here we go. Given the reduction of window screen tops most commonly used for herp tanks, would it be better to bump up the %'age of UVB output to make up for the reduced penetration? So if a 5.0 is recomended for my lizards and I'm getting a 30% reduction due to screen type, Should I be using a 10.0 or 12% bulb to get better penetration for a better UVB source for my lizards? Due to the scittish nature of my swifts I cannot have an open top or have a light inside the tank to get the direct lighting you could get from a larger open enclosure.