I have a Boaphile rack system and it is made w/ only .050 ( less than 1/16 of an inch) all way around the top of each tub and the air flow seems good. And they seem to have enough air, no bad smells linger and the humidity stays good.Originally Posted by MarkS
I didn't think it was enough air at first but it seems to be working out fine.
A lot depends on the room conditions where the tub is at.