There is a tiny piece of krausen left of from a Wyeast German Ale fermentation. This little thing has survived multiple PBW soakings that easily obliterated everything else. I scrub it with a soft red brush for plastic carboys and it barely takes anything off. Any advice for finishing this piece of crud off? Should I even be worried? After a few weeks + PBW and bleach soakings I doubt anything is still alive in there. Sorry for the terrible pic I only have a phone camera and lighting is hard a night.
PBW works on organic material. It is probably beer stone, use acid on that. Star San or Distilled vinegar would do the trick.
