The foam did build up again yesterday after its disappearance following the initial addition of fermentation pressure, but now it’s receded almost to nothing and the collection jar on the bottom of the vessel is full. The spunding valve isn’t hissing as much this evening as it was 12 hours ago, so I’m wondering if we’re already getting towards the end of fermentation after just 2 days? That seems impossibly quick. I’m also wondering how I’ll add the two bags of hops without letting in oxygen, and whether the jar’s full enough with trub to interfere with the butterfly valve when I come to dump it after cold-crashing.
There are still some fresh foam bubbles in the middle of the surface and I can see occasional bubbles crawling up the inside of the collection jar, so clearly the yeast is still doing its thing and I needn’t think about taking a gravity reading just yet, which I’m quite looking forward to since it should be very easy using the picnic tap. I do want to get the hops in there before the yeast stops producing CO2 altogether since that’s a partial insurance against oxygenation, though I suppose that CO2 that I bubble in via the dip tube after dry-hopping will displace any oxygen that’s inadvertently introduced since oxygen is lighter and will exit via the spunding valve. Might be worth minimising the oxygen in the hop pellets somehow.