I have never seen that either personally. Agar, grain jars always have loose foil after sterilization. Comes off pretty easily once I am ready to spawn/inoculate with one hand.
The foil is only there to protect the moisture content of your substrate. If not using modified lids, there is really no need to use foil (but I always do just out of habit). Especially if the jars are way above the water line.
And the foil does not “create an air tight seal”. I have personally used 2 layers of foil only before cause I had no lids and was too lazy to get my [email protected]
$ to the store lol. And there was never a tight seal.
My 2 pennies.
Edited by peacefrog, 06 September 2020 - 05:47 AM.