I have a 152quart igloo cooler that I use. I set it on end (drainhole down) since it has slots in it, I added metal shelves (from the modular shelving you can build) Three satche bags with beads from Heartfelt (Thanks Viper) and two oust fans.

Then with cigar boxes and bundles hold steady at 65%

note: The oust fans run for 5 minutes the off for 15 minutes, so the air is in constant motion.