I swear man youse guys are really making a mountain out of a mole hill. You think teas are a new thing? We started out just brewing them in a tub. Whenever you walked by you would give it a stir. Next thing you know, in the wake of legalization, everybody and their brother is becoming an expert and they all got a better way. I use an air pump. Somebody else uses a water pump. I used to use a canoe paddle. Get your microscope out and count the microbes then let me know which ones the best method.
Then figger out how to make aerobic and anaerobic bacteria thrive together!
Actually this occurs when you brew EM1 in the head space of the gallon container. It is not filled to the top to allow for gas expansion, and in that space is a transitional area where both meet and thrive