After hearing good things on this forum about combining Windsor and Notty for bitters, I did so, and the fermentation is doing fine on day 4--and the aroma is great.
But I noticed something curious earlier today--after the airlock activity had fallen to about 5 bubbles per minute yesterday, today it shot up to 13 this afternoon, even though the krausen had started to drop and the beer was clearing in places. But tonight, it was back down again--to 2, and so I'm just wondering what might have happened/ I'm not alarmed at all, just curious.
Could it be that one yeast operates at a different schedule? I've had experience with Burton yeast rising, dying, and rising again, so maybe this was a minor version of this phenomenon.
Any insights would be appreciated.