What exactly is that called?
I have a video of one in action, but I can't get it to upload. I filmed it on my android phone and I suspect the file type is not supported.
What exactly is that called?
I have a question for the group. Rather than a single hit of pure oxygen at pitching time and getting the concentration high enough to get the yeast though their growth phase, why not simply bubble air through the diffuser at a lower oxygen content but just maintain it for the important first 24 hours? Filtered of course. Don't worry about a magic concentration, just make plenty available while they are reproducing. Reasonable?