I don't know exactly how the smell issues works. My burms, retics, boas, balls, everything are SIDE by SIDE with my rat racks. I mean literally: Burms Cage - 2" gap - Rat racks - 2" gap - Rack Systems. My retics especially tend to end up on top of the wire mesh of a rat cage while i'm trying to hold them and clean sometimes and they come right out when I pull them away and are always just exploring, never trying to eat the rats. Now, Wednesdays when I have a bucket of frozen rats thawing in front of their rack for a few hours..... You better open the tub with a hook or get a gnarly bite to the face LOL