Just to chime in Mike, I keep mine on a carpeted floor. One thing I noticed also is the direction of my ceiling fan makes a difference. I know that in the winter the fan is supposed to spin so it blows upwards and in the summer it blows down. This is really kinda wierd to me but as long as my fan spins in winter mode (blowing upwards) my temps and humidty are perfect. If I change the direction of the fan everything changes in the tubs. It took me a few days to realize what was going on. I didn't add any more holes or change rack location or anything else. I started getting PO'd then I remembered that I changed the fan direction. Once I changed it back everything went back to normal.![]()