[BlindedByScience]

Double thumbs up on the Bovida cal kit. They are very cool and you can trust them.

Only other thing I'd add is it's lots better to run the test in a big glass jar of some type than it is in a bag; I sure get far, far more consistent results that way. Mason jar, old mayo jar, etc....works perfectly. If you're stuck with plastic bags, I'd double bag the test environment. I've done it that way, too, and it seems to work more consistently.