My QT racks are 32 qt four drawer racks. I have dividers that will turn the 32 qt tub into two 16 qt spaces. If I get baby or juvenile snakes, I use the divider. If I get an adult, I use the 32 qt tub. You do need some flexibility in your quarantine racks. If that is what you are asking, rather than QT as quart. Hard to tell from the post if you are asking about quarantine or quarts.

If you are asking about quarts, I use 6 quart tubs for babies. When they out grow them, I move them straight into a 41 quart tub with a hide. If they go off feed, I have a few 32 quart racks in my reptile room that I can move them down to. So far, I've rarely used the 32 quart racks. They seem to do well going from 6 quart to 41 quart as long as they have a couple of hides.