[swords]

One website I was reading they used an "H" and "U" glass profiles to make a grate under the window to reduce fog here's the link, scroll down and click "Air (Ventillation)" page it's at the bottom:

www.poison-frogs.com, a 2002 website full of information on dart poison frogs, vivaria, plants, together with lots of pictures, films and more. Orchids, bromelia's, mosses, descriptions of dendrobates leucomelas, azureus, pumilio, tinctorius, auratus

Not sure if I need to go to a glass shop to find these or what cos the hardware store guys just look at me like I'm nuts when I ask for stuff.