Air holes in rack???

[TheSnakeGuy]

I would also say hole too just tops do not ventilate well at all. The general formula is 7 times the side height to get clean non turbulent air. If the tub is 5 inches hight the clean air starts at 35 inches along the bottom away from the sides.

I use the rule if the water bowl is removed and the substrate is dry the rh should be equal of the room in less than one hour. Just top hole almost always fail the one air change per hour. (10 times less than a class room is allowed)

I read this over about 4 times and I still don't understand what they're trying to say. Anyone else understanding this? ^