Stuck Fermentation? Krausen and Airlock Activity, Minimal Gravity Change

[goblueram]

Hi there - long time lurker but just signed up on the site and hoping for some help. Obviously this site has an abundance of great information, a ton of which I have used over the course of a year and a half of brewing. I've tried searching for this one but it seems to only turn up the exact opposite problem (no krausen/airlock activity, but gravity changing). So here we go...any thoughts would be appreciated!

I am a BIAB brewer and did my version of 5 gallons of Centennial-hopped IPA (Bell's Two Hearted-like). The grain bill was as follows

• 10 lbs Pale Two Row
• 3 lbs Pilsner
• 2 lbs Crystal 40

I mashed at 152* F for 60 minutes. I pitched re-used slurry of US-05 that had a 24 hr starter using leftover wort. Here are the samples, readings, and steps i took during fermentation:

• Day +0, 1.072, which was 69% efficiency
• Day +14, 1.032
• Day +16, 1.032, heated to 72*F and rouse yeast
• Krausen rises and signs of airlock activity
• Day +19, 1.030
• Krausen has not fallen, signs of activity
• Day +22, 1.030, pitched rehydrated US-05 at 69*F, slowly added beer to the hydrating yeast in order to acclimate to alcoholic environment (maybe?)
• Krausen rises and signs of airlock activity
• Day +27, 1.026
• Krausen has not fallen, signs of activity
• Day +29, 1.026, attenuation 63.9% which is way low for US-05

So now the dilemma is what is actually happening in the periods where I am visibly seeing activity, but not losing gravity points?

Is this a stuck fermentation, or is it just completed as far as it will go?

What were the factors that contributed to the FG (if this is FG) staying so high?

• Mash temp (thermometer) - we brewed 2 batches the same day, and one fermented fine with higher attenuation. checked thermometer against digital probe and it looks fine.
• Fermentation temp - again, 2 batches fermenting right next to each other
• Unfermentable grain - base malts are 87% of grain bill, should be fine right?
• Wrong grain - this is a shot in the dark. Did I pick out the wrong stuff? Unlikely given LHBS is the best (Adventures in Homebrewing)
• Viability of yeast - the re-used slurry could've been an issue, but then added a fresh packet of US-05
• Hydrometer calibration - reads 1.00 in water (picture)

Any ideas or help would be appreciated!

 

[jan_b19]

as long as there are visual signs of fermentation it's not stuck. give it a while.
if nothing changes try giving the carboy a swirl, there might be a lack of oxygen in the beer.
add some yest nutrients. keep the carboy at a nice 70*F


Grain bill looks ok.

 

[BlueHouseBrewhaus]

Try a swirl again and give it more time. If it's still stuck you could try some amylase enzyme to get it restarted.

 

[Master]

Does your hygrometer read near 1.000 in water?

Thought I had a stuck once.

Paper inside the hydrometer had slipped.

 

[goblueram]

Are the pictures showing up in the post? The hydrometer is right at 1.000 in the water. Picture might be a little small, I resized so it wasn't taking up so much space.