I forsee heat, size, and smell as the biggest problems here. Need to get outta that tub, it seems too hard to grow 2 or 3 plants in there at once especially if you wanna keep it looking natural. May I suggest a carbon scrubber right behind a 120mm computer fan. And try buying a small little handfan at Wally World to keep the airflow in te box moving. It's what I do and those things work perfectly, no strong winds to hurt babies, but plenty of circulation if put in the right spot.