Stuck fermentation?

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BDRJ

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I brewed up a Kolsh style beer last Friday and I am not sure it fully fermented or might just need more time.

I did a partial mash with
2.2kg of pilsner malt
500g of Munich malt
2lbs of dry pilsner extract
2 oz Hallurtau
2 packs of Lellemand Koln yeast.
OG was 1.042

Fermented at 64F and after 3 days the airlock activity all but stopped so I moved the fermenter upstairs where it has been at 68F since.

Checked the gravity yesterday and it was only at 1.020.

Just wondering if the fermentation is stuck or just needs more time.

Thanks in advance.
 
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"Last" Friday meaning 2 days ago or 9 days ago?

If the latter, what's the current gravity?
 
Last Friday so just over a week ago.
Tested the gravity yesterday and it was 1.020
 
Last Friday so just over a week ago.
Tested the gravity yesterday and it was 1.020

I see you added some details to the original post. I'd give it a couple days and check again. I'd bet it's still slowly moving along. You're using a hydrometer, right?
 
I see you added some details to the original post. I'd give it a couple days and check again. I'd bet it's still slowly moving along. You're using a hydrometer, right?
I am using a refractometer
 
Ahhh well there is something new. I thought it was already calibrated for some reason. Will have to do a bit of research then. Or just use my hydrometer
 
That does seem slow. You pitched plenty of healthy yeast, it's a reasonable OG, and it's a normal temperature. You really shouldn't be having fermentation problems. It sounds like you did everything right.

The only thing I can think of is a yeast issue. Was the yeast expired, or any chance it was exposed to heat? Also, can you deduce anything from the smell? Strained yeast give unpleasant aromas. If you get some strange aromas you may want to pitch some extra.

Or maybe it's a refractometer issue and your beer is just fine!
 
Ahhh well there is something new. I thought it was already calibrated for some reason. Will have to do a bit of research then. Or just use my hydrometer

It's not about calibration. It's (mostly) about the fact that alcohol skews refractometer readings. Since you have already taken an original reading and a current reading with your refractometer, just plug those two ("brix") readings into part II of the linked calculator and see where you are. No research needed.
 
That does seem slow. You pitched plenty of healthy yeast, it's a reasonable OG, and it's a normal temperature. You really shouldn't be having fermentation problems. It sounds like you did everything right.

The only thing I can think of is a yeast issue. Was the yeast expired, or any chance it was exposed to heat? Also, can you deduce anything from the smell? Strained yeast give unpleasant aromas. If you get some strange aromas you may want to pitch some extra.

Or maybe it's a refractometer issue and your beer is just fine!
The one package of yeast was close to being expired however it was in my fridge the whole time not anywhere near heat.

The beer actually tasted quite good and light in body so I got that right.
 
It's not about calibration. It's (mostly) about the fact that alcohol skews refractometer readings. Since you have already taken an original reading and a current reading with your refractometer, just plug those two ("brix") readings into part II of the linked calculator and see where you are. No research needed.
Ahh that makes more sense. Thank you! Looks like it is at 1.007 according to the correction. Will take a hydrometer reading before bottling to see if it matches. Thanks again.
 
Ahh that makes more sense. Thank you! Looks like it is at 1.007 according to the correction. Will take a hydrometer reading before bottling to see if it matches. Thanks again.
Sounds like you solved the problem. Congrats! Be sure to post tasting notes when you pour it. I'm planning to brew a kölsch in February and can use some tips.
 
Sounds like you solved the problem. Congrats! Be sure to post tasting notes when you pour it. I'm planning to brew a kölsch in February and can use some tips.
Ya will do. I actually added in the DME late in the boil and mixed it with some warm water in a separate pot so I got all of it without it clumping up due to steam. It also seemed to help with the color not being so dark.
 
The only thing I can think of is a yeast issue. Was the yeast expired, or any chance it was exposed to heat? Also, can you deduce anything from the smell? Strained yeast give unpleasant aromas. If you get some strange aromas you may want to pitch some extra.
Would you suggest the re pitching the same strain or something different? I think I pitched some unhealthy yeast and it stalled.
 
Deleted... (I had answered @Civilian's post as if he were the OP. Doh.)

New answer for @Civilian... personally, I would recommend almost always repitching the same strain if the issue is believed to simply be a bad original pitch. You selected that original strain for a reason, right?
 
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