1.080 finished in 2 days on YeastCake?

Here's my worry, this was my first batch that I attempted to re use my yeast cake, US-05(from a cream ale) & let my Imperial IPA go right on top.

So, 2 days ago I brewed(extract/specialty) & cooled the IIPA, racked off the cream ale, dumped 2.5 gallons of PDX,OR water in the fermenter and funneled the rest of the wort on top. Shook everything ALL together(cake too) for additional aeration and let it rest.

Now I did have some immediate bubbling on my blow off, but nothing massive and it stayed quick and steady all day. The krausen head did reach the top of the 6gal bucket, but never exploded or went crazy out of the tube. Fast bubbling the second day as well. Now, Saturday morning, bubbles were almost gone so I took gravity as I was concerned they'd stopped. The reading was 1.016!! I almost couldn't believe it.

So, did it actually finish out that quick? It tasted ok, albeit it green/bitter.

Any comforting thoughts from anyone? Or worries.

ryan
NoPo, oregon

Your gravity might not drop much more, but I would leave it in the Primary for at least another couple of weeks to allow any final fermentation, and to let the yeast do their other 'jobs' as well (preventing diacetyl, etc.)

I've found that beers on yeast cakes take off and ferment out really quickly. Although there is a lot of dead yeast in the cake, there is tons of viable, active yeast.

this is how all fermentations should be: healthy! i recently did a RIS and it finished the major fermentation in like 2 days as well, OG of 1.102. you'll need more time just to let the yeast clean up a bit, though. i typically do an initial small beer with a 1L yeast starter, then a big beer with the yeast cake i wash outta the first beer.