I actually did just that this past week to make a QT rack for two boas. The tubs are the 52-qt under-bed style from Hefty. They have handles that come up and hold the lids down securely, and they have a few extra inches of length & width over the 41-qt tubs so they're an ideal size for young adult boas.

If you want to stick to using Sterilite tubs get the latch boxes rather than the tubs with the lids that lift off easily.