Yes, exactly. I just picked up a 200gal for my SINGLE cornsnake. It's an absolutely massive tank, but I couldn't imagine putting more than two snakes in it, and if I did it would ONLY be after the tank was split in half so they didn't have access to each other. In my opinion, a full grown corn needs a 55gal (or more) in order to have enough space to adequately move around and find a temperature zone of their liking. I can't imagine how crammed those six snakes must be, and like you said, it definitely doesn't sound like she minds adding even more to it.
Not to mention, she said it was a cube tank. Cornsnakes aren't arboreal snakes (well, mine isn't at least lol), how is all that vertical space going to help them at all?
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