If these will work over glass tops, I'll take them, if they haven't been spoken for already. I have a 55gal with Coralife-type light, and now I just use little wood blocks to raise the lights off the glass.
Nikki, these will not work on glass tops. Ill be psoting a pic in a bit and do my best to show why these are mainly for open top aquariums. Unless you custom cut the glass its highly unlikely they will work with glass tops.