I'm using a 55 gallon natural set-up...it has two hoods with built in light fixtures. Since the cresties need to have ventilation I drilled rows of 1/4 inch holes across the top to simulate a screen top. I then run a small clip fan to air it out to prevent mold. I like the look of it better than a screen with a light sitting on top. It has a very nice contained clean look. Is anyone else doing anything like this? It seems to be working well.

