Here is a great source for UVB information..its good reading

UV Guide UK - Ultraviolet Light for Reptiles - UVB reptile lighting on test

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MARSHA

:D I'm smiling because I have no idea whats going on!

As long as the screen top has openings a minumum of 1/8 inch or larger you will be fine.
It is the fine mesh, window type, screening that is a problem with shading out your UVB
It can get confusing!
The problem is that with flourescent type lighting the useable UVB drops off with distance. Anything over 10-12 inches from the bulb is pretty much useless for a basking diurnal lizard. The flourescent tube generates light along it's entire length and so will cover the entire length of the tank while the compact only emits light from a single small area.

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Merlin,
What's Life Without A Little Magic!

Gotcha. Its the type of lid readily available at pet shops, its not window screening.. You know the ones, metal and black.

And that makes sense about the tubes vs CF. I Have plenty of fluorescent hoods around, but I already bought this CF and they wont let me return it. Like I was saying, maybe Ill get a tube for the swift and use the CF for my smallest tank with the dwarf geckos.

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One nation under Dog
RIP Chameleo Extevez
Dog is my copilot.