Lots of fermentation stuck at 1.020

[TurnipGreen]

I have an alt stuck at 1.020 for about two weeks now.

I studied a pile of posts and my brewing notes to try to figure what caused the stuck ferment. I'm pretty sure mine is stuck because of general yeast health. I'm gonna try raising the temp for a week or so. If that doesn't work maybe I'll try racking it onto a fresh yeast cake.

But I noticed there are a pile of people that get fermentation stuck at 1.020 and that's where it's gotten stuck for me another time as well.

Anyone else have multiple brews stuck at 1.020?

Anyone have an idea why 1.020 is such a cursed gravity?

 

[NorthwestBrewman2013]

Depends on a few things:

OG
Was there a starter?
Yeast type?

These three go hand in hand. If you had an OG north of 1.075 and you didn't make a starter and didn't at least throw 2 packs of yeast into it, your yeast may be too stressed.

 

[bransona]

Are you using extract? 020 is the magic number for extract sometimes. Hits the wall like a flaming bus full of flaming busses and stops dead in its tracks.

 

[MeanLowerLow]

I had my pliny clone get stuck around 1.020 - I pitched some dry safale US-05 yeast and voila, fermentation restarted and nailed my fg.

I'm curious - are you using a fermentation chamber or some other temperature control method? Are you making starters?

 

[TurnipGreen]

I'm doing all grain. The first time was my first attempt at a lager and I'm almost certain my starter was too small.

This recent one was a mess of a brew day. I ended up using dry yeast and the OG was 1.071 I should have used two packets especially since I kept the fermentation on the cooler side.

But still, why is 1.020 that flaming wall all those flaming busses run into?

I've only ever had these two beers get stuck and they have both been 1.020.

I think know why they are getting stuck but why don't they get stuck at 1.030 or 1.025? It seems like 1.020 is a pretty common gravity to get stuck at.

 

[nyer]

I have had the same issue since moving from ny to florida. The only changes I've made should be positive ones, I now have a temperature controlled fermenter, I use starters (usually washed yeast), I chill as fast as possible by pumping ice water through an immersion chiller and I use treated distilled water. Everything stops at 1020 and if I use us05 I'm getting a bit of bubblegum now. Damned if I know. I have 10 gallons of kolsch fermenting now and will be very upset if it stops at 1020 too.

 

[bransona]

This answer may not help much, but may lead you to a better answer.

I think it comes down to fermentability of the extract. It varies, and can be different from what the manufacturer says. Apparently there is also a variance between dme and lme in relation to the wall. Hopefully these points lead you to Google. Look up your specific extract, other similar experience, etc.

 

[nyer]

This answer may not help much, but may lead you to a better answer.

I think it comes down to fermentability of the extract. It varies, and can be different from what the manufacturer says. Apparently there is also a variance between dme and lme in relation to the wall. Hopefully these points lead you to Google. Look up your specific extract, other similar experience, etc.

Hmmmm, I did switch from Austin homebrew to a local shop.

 

[TurnipGreen]

I've also just started using temperature control.

I try to limit the number of samples I pull, but I might start pulling more to try to start raising the temperature based on that. If I understand the other posts that would be at around 50% attenuation. I have been just controlling the temps until the krausen starts to fall then start warming.

 

[TurnipGreen]

Fermentation on my alt picked up again at room temp. I was down to 1.014 yesterday. I'm going check it again later this week and maybe bottle next weekend.

 

[JayDog]

Are you checking with a refractometer or hydrometer? A refractometer will show 1.020 or 5 brix as a final gravity. The actual gravity is lower. You can enter all your numbers on northern brewers website. Search for a refractometer calculator online and it will show up. If you are indeed checking with a hydrometer then I have no idea. Maybe too high of an og.

 

[VeloxGuy]

This just happened to me, a red ale stuck at .02 for a couple weeks. It restarted when I gave the carboy a slight shake. I then cleaned a racking tube and swirled up the yeast cake and it has started right up again and is slowly chugging away. Was pretty careful not to introduce O2.

Try swirling and moving the yeast around.

 

[nyer]

I think my issue was the washed us05 I was using. My ipa and pale ale both stopped at 1020 using it and they both have a slight bubblegum flavor. They are surprisingly good and maybe I'll just pretend I was making a belgian pale ale. I just took a gravity reading on 10 gallons of kolsch I made using new wyeast 2565 and ended up right at 1012 where it should have. I'm dumping the rest of the washed us05 I have and I'll start new on the next ipa.