I have an orchidarium (the Grande Cayman) and I find the air is pretty stale if I don't leave the doors cracked open a tad. Matter of fact, I wish I could build my own as there are several things I would change, like adding a drainage system, the little rubber trays just collect water that just stay stale as well. I love my orchidarium, don't get me wrong, but for the price, it seems to be lacking several features. I've also added a misting system since I couldn't keep my humidity up high.
Mistking
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