I learned the hard way that it is not OK.
A bit of background: I have an advanced degree in epidemiology (study of disease in populations). My areas of expertise are in chemical and microbial exposures to humans. I am a frequent speaker and have authored articles for highly reputable scientific publications on microbial growth in indoor environments and exposure to populations within those environments.
So...in my drive to get the perfect cham setup I purchased a large screen enclosure later to find out it would be way too big for the 2.5 month old cham I was getting. Instead of buying another small screen enclosure I decided to go with a 29 gallon glass aquarium. Figured it would be perfect and help have better control of temperature and humidity until winter passed. Some on this forum advised me against it. But dammit - I know what I'm doing when it comes to controling microbial growth. So I kept him in the glass enclosure. Two weeks ago (cham was 3.5 months old) I spent about $80 on vet bills and a whole bunch hassle and time trying to clear up an upper respiratory infection. My chamleon's infection cleared up (after 2 weeks of treatment). I study humans not reptiles but that did not prevent my ego from getting in the way. I did not listen to those who know chams and got a credit card bill and a bunch of head aches in return.
I know what caused the problem. Lack of ventilation, moisture and organic material in the glass aquarium (and this was 3 times larger than a 10 gallon with more top surface area for air exchange). I've since moved him into his large screen enclosure, am cup feeding and keeping a close eye on him. There are some on this forum that think my enclosure is now too large for a 4 month old.....but dammit, I know what I'm doing

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