I use that on the back of mine. I would also on the sides, except that's where the doors are. Mine is rather large, so I need two doors. It does tend to get moldy after a while, so a spray with Physan 20 and that clears it up for 6 months or more.
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Ross
http://orchids-ross.blogspot.com/
I don't do most Dendros or large, "floofy orchids". For me it's minis (like Angraecoides), Masdies, Paphs, and others that crept in somewhere along the line. See my orchid list for complete collection (usually not current.)