So, my BP has been successfully transitioned to his new PVC enclosure (more on this in another thread), and I find myself with an empty 36x18x12 Exo-Terra. Now, having learned the hard way that this tank really doesn't work well for snakes with slightly higher heat and humidity needs, I am trying to figure out who will get the vacant space.

My first inclination was to use it as a temporary enclosure for a BCI, then move it to a PVC also, and I may still go that route, but I am also looking at colubrids that may be fine in this type of enclosure for the long haul. Two that I have taken particular interest in are the Mexican Black Kingsnake and the Grey Rat Snake. Obviously, this leads me to some questions that I felt could best be answered by the group here.

When keeping kingsnakes, Mexican Black in particular, can they be in close proximity to other snakes? I know about the "don't handle them right after handling another snake" rule, and the basic quarantine procedures, but what I am trying to determine is whether or not I could keep one in an enclosure stacked on top of my BP enclosure, or would the smell of the other snake lead to behavioral issues?

Also, does anyone have experience with grey rat snakes? I found a "white oak" grey rat snake on MM that has a really nice pattern. From what I gather, they are semi-arboreal, so I would assume a 12" tall enclosure won't cut it past the hatchling stage, but I am interested in knowing if anyone has dealt with them, how the temperament is, any special considerations, other enclosure specifics, etc.

I apologize, I may have tried to stuff too much into one post here.