problem- he's told me he has strained it when pouring into fermenter, and now says he has a green-gray layer of scum on top of white krausen. I think this may be just the beloved scum ring, but am wondering if anyone has had this kind of mold grow whilst fermentation is in progress.
Could a mold live under the these conditions? the brew is still bubbling away so alcohol levels would surely kill any bacteria, right?
the only beer i've had trouble with was a bavarian lager, had some white patches on the surface of the beer, but bottled and drank anyway

b