Heather,
I am not looking for any answers, the answer is no mixing as a hobby, just a discussion on the topic. So what is it that a herpetologist does at a zoo when they decide to mix in an enclosure nearly the same size as a hobbyist? Weekly exams? Just curious. On the few occasions that I have seen mixing at zoos, it has been with PDFs in what I thought was a pretty small enclosure.