Fermentation FG problem?

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Attwell

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So after 2 weeks in the fermenter I decided to take a FG reading and it's come in at 1.020 when it's supposed to be at 1.012, at the start of fermentation for roughly 4-5 days it was bubbling away had a lot of krausen at the top but now that has dropped down to the bottom. I have raised the temp to 20 celcius, it has been at 18 the whole two weeks. Not to much activity since raising it I don't think, would adding another smack pack of London III do the trick?
 
So after 2 weeks in the fermenter I decided to take a FG reading and it's come in at 1.020 when it's supposed to be at 1.012, at the start of fermentation for roughly 4-5 days it was bubbling away had a lot of krausen at the top but now that has dropped down to the bottom. I have raised the temp to 20 celcius, it has been at 18 the whole two weeks. Not to much activity since raising it I don't think, would adding another smack pack of London III do the trick?
Reading with a hydrometer or refractometer?
 
Double check hydrometer reads 1.000 in water. What was the recipe, OG and mash temperature? It could be that not enough yeast was pitched and it's given up, in which case pitching more yeast may help. You could try rousing the yeast first with a sanitised spoon and see if they finish the job. If the recipe had a high OG and a lot of unfermentables / high mash temperature it may be finished. Check the FG over the next few days.
 
Double check hydrometer reads 1.000 in water. What was the recipe, OG and mash temperature? It could be that not enough yeast was pitched and it's given up, in which case pitching more yeast may help. You could try rousing the yeast first with a sanitised spoon and see if they finish the job. If the recipe had a high OG and a lot of unfermentables / high mash temperature it may be finished. Check the FG over the next few days.

Use RO water to check the hydrometer? OG was 1.058 & mash temp was around 65-68 Ish at most. I pitched 232 billon cells which I got from a calc for this recipe so two and a bit smack packs.
 
Use RO water to check the hydrometer? OG was 1.058 & mash temp was around 65-68 Ish at most. I pitched 232 billon cells which I got from a calc for this recipe so two and a bit smack packs.
Not wishing to sound mean or anything, but was the mash temp 65 or 68? It does make a difference.....

One time I mashed at 70degC and it got down to 1.018 or 1.019 (Wyeast 1275) - the mash temp does seem to have an effect on the FG, and certainly in my case Brewers Friend doesn't reflect this properly.

For a mash temp of 68 I'd expect to get down to something like 1.014 though, maybe not quite 1.012.

How does it taste? Does it taste "done"?

I'd say give it another week and see - it might just be taking it's time to get down those last few points - I normally just leave mine 3 weeks in any case, no point trying to rush it.
 
If it doesn't attenuate further, I would rehydrate a sachet of champagne yeast and use that to dry it out. Champagne yeast is quite neutral and won't add any flavour of its own. Your Wyeast has already given the beer its character and this will not be lost. Alternatively, (and as I write, I think this would be my favoured option) Fermentis do a bottling yeast SafAle F-2 20. "Profile: selected specifically for secondary fermentation in bottle and in cask. This yeast assimilates very little maltotriose, but assimilates basic sugars (glucose, fructose, saccharose, maltose)."
If that doesn't lower the FG, then it has fermented as far as its going.
 
If it doesn't attenuate further, I would rehydrate a sachet of champagne yeast and use that to dry it out. Champagne yeast is quite neutral and won't add any flavour of its own. Your Wyeast has already given the beer its character and this will not be lost. Alternatively, (and as I write, I think this would be my favoured option) Fermentis do a bottling yeast SafAle F-2 20. "Profile: selected specifically for secondary fermentation in bottle and in cask. This yeast assimilates very little maltotriose, but assimilates basic sugars (glucose, fructose, saccharose, maltose)."
If that doesn't lower the FG, then it has fermented as far as its going.

Any certain type of champagne yeast?

Not wishing to sound mean or anything, but was the mash temp 65 or 68? It does make a difference.....

One time I mashed at 70degC and it got down to 1.018 or 1.019 (Wyeast 1275) - the mash temp does seem to have an effect on the FG, and certainly in my case Brewers Friend doesn't reflect this properly.

For a mash temp of 68 I'd expect to get down to something like 1.014 though, maybe not quite 1.012.

How does it taste? Does it taste "done"?

I'd say give it another week and see - it might just be taking it's time to get down those last few points - I normally just leave mine 3 weeks in any case, no point trying to rush it.

I agree, one of my issues was not recording anything... Rookie mistake.
 
Depends on your SG but London Ale III can be a little middle road attentuator.. I personally wouldn't want to dry the beer out too much as part of the wonderful yeast is that it helps give teh beer a slightly fruit sweet bready taste.. I have had mine finished 1014-1016 with that..

Have you tried some aggitation?
 
Depends on your SG but London Ale III can be a little middle road attentuator.. I personally wouldn't want to dry the beer out too much as part of the wonderful yeast is that it helps give teh beer a slightly fruit sweet bready taste.. I have had mine finished 1014-1016 with that..

Have you tried some aggitation?

I've raised the temp so I'll see what my reading is next Sunday if it hasn't moved much do you think adding another smack pack or using champagne yeast would be a better option?
 
I've raised the temp so I'll see what my reading is next Sunday if it hasn't moved much do you think adding another smack pack or using champagne yeast would be a better option?
Raising the temperature's good. Giving it a good rousing is better. Get a big sanitised spoon or paddle and stir the whole lot up to get the yeast back into the beer. If that doesn't work then use a finishing yeast- it won't take anything away from the flavours you've already got.
Somebody asked earlier: what does it taste like? Does it taste ready? If it does, it probably is!
...and next Sunday is a bit far away. Give it until Tuesday or Wednesday.
 
Raising the temperature's good. Giving it a good rousing is better. Get a big sanitised spoon or paddle and stir the whole lot up to get the yeast back into the beer. If that doesn't work then use a finishing yeast- it won't take anything away from the flavours you've already got.
Somebody asked earlier: what does it taste like? Does it taste ready? If it does, it probably is!
...and next Sunday is a bit far away. Give it until Tuesday or Wednesday.

Thank you for the help, means a lot.
 
Raising the temperature's good. Giving it a good rousing is better. Get a big sanitised spoon or paddle and stir the whole lot up to get the yeast back into the beer. If that doesn't work then use a finishing yeast- it won't take anything away from the flavours you've already got.
Somebody asked earlier: what does it taste like? Does it taste ready? If it does, it probably is!
...and next Sunday is a bit far away. Give it until Tuesday or Wednesday.

Safbrew F2 is used for bottle conditioning so would I just add the yeast to the bottling bucket then bottle or add it to the primary for a few days then bottle?
 
Safbrew F2 is used for bottle conditioning so would I just add the yeast to the bottling bucket then bottle or add it to the primary for a few days then bottle?
If you have another fermenter, rack the beer off into that. Rehydrate the yeast according to the instructions attached, but don't add the priming sugar at this stage- you've already got too much sugar, the question is whether it's fermentable sugar. Pitch the new yeast slurry into the beer and keep it in a warmish place. If and when your FG reduces and remains stable for a couple of days, then add the priming sugar and bottle.
It's important to rehydrate this yeast first.
https://bsgcraftbrewing.com/Resources\CraftBrewing\PDFs\Product_Sheets\Fermentis/fermentis_safbrew_F2.pdf
 
If you have another fermenter, rack the beer off into that. Rehydrate the yeast according to the instructions attached, but don't add the priming sugar at this stage- you've already got too much sugar, the question is whether it's fermentable sugar. Pitch the new yeast slurry into the beer and keep it in a warmish place. If and when your FG reduces and remains stable for a couple of days, then add the priming sugar and bottle.
It's important to rehydrate this yeast first.
https://bsgcraftbrewing.com/Resources\CraftBrewing\PDFs\Product_Sheets\Fermentis/fermentis_safbrew_F2.pdf

Checked the gravity today and hasn't moved at all still at 1.020 even with a stir etc so going to have to add champagne yeast then.
 
I think I would bottle it. Don't know why your FG's so high, but it's stable and if it tastes ready, I would say it is ready. Bottle some of it in PET bottles so that you can keep an eye on how the pressure's building up. Just in case.
 
I agree with @An Ankoù - you'll probably be fine but, just to be on the safe side, once they've carbonated I'd store these bottles as cold as possible, inside a box, lined with a bin bag, and with a lid on. Bottle bombs, as the name implies, are dangerous.
 

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