Tupperware is a great item and there are those just like humidors that tend to work better than others. I've had that kind where there is the clasp on top...those aren't "airtight" as much as they are "almost airtight".....RubberMaid is "airtight" and there is the 2.5 gallon size that sells for $11 and I know WM will take back anything you've bought and exchange if you wanted to...just sayin as I've tried the top clasp and it will leech air..slowly. The clasp isn't like a seal... a seal is all the way around and when you line the bottom with cedar you are pretty much guaranteed no issues. The foam is another issue....it will cause mold growth after about a year and you will see a slimy substance start on that foam before a year is out. Boveda, Beads or KL is a great way to ensure that you not go through what a lot of us have in the past....just want to let you know before you continued. JMHO