I'm in the process of planning a small terrarium/grow tank. The current idea is to use an 90cm/36" ExoTerra tank with a plexi glass top plate. And 4x 24W T5 tubes for lighting.
How much heat will the lights generate? Will I (or the plexi glass top) get into trouble/melt if I place the fixture directly on top of the plexi glass top? Would it be better to mount the fixture in a hole in the top plate?