How do I determine when I've hit FG?

[MountainGoatBrewing]

Basically, outside of guessing and/or looking at bubbles in the airlock, how does one tell when fermentation is complete?

Do I open the primary as soon as I see no bubbles and siphon a bit off and take a reading with a hydrometer?

I'm flipping back and forth on whether or not to rack to the secondary or not, but if I do, I'm curious as to when I can determine the proper time to do it. I want to dry hop as well, so knowing when it's done is still relevant, even if I just keep it in the primary.

Any thoughts on racking vs. not racking with London 1968 ESB? Does yeast matter?

Attenuation is 67-71%, according to the package.
The estimated OG was 1.068, and the actual is 1.060.
FG is estimated to be 1.021.
It's been fermenting at 65º for 4 days at present.

My other main consideration with this yeast is diacetyl rest. From what I've read, I should wait a couple of days at a slightly warmer temperature to let the yeast clean up after fermentation is done, but what if I don't rack to secondary? When would I do the D Rest???

Thanks in advance.

 

[beerman0001]

Leave it in primary for at least 2 weeks. Check it with your hydrometer for 3 days in a row if the sg has not changed then it is done. D rest is for lagers. There are pages of post on racking or not racking in the end it is up to you to decide.

 

[MountainGoatBrewing]

Much obliged.

 

[C-Rider]

Leave it 3 weeks then do as above.

 

[MountainGoatBrewing]

Checked it today (it's been 8 days). 1.024. Seems a bit high, especially since the OG was lower than anticipated.

 

[BucksPA]

a hydrometer is one of the best ways to check on your fermentation. airlocks, bubbles, etc are different for every fermentation and because you do not see any visual signs of fermentation does not mean it is complete. every yeast is different as well and some strains ferment vigorously and quickly while others do not.

the summary of this: Use a hydrometer!

good luck

 

[C-Rider]

Checked it today (it's been 8 days). 1.024. Seems a bit high, especially since the OG was lower than anticipated.

wait two more weeks. Then try measure again.

 

[Golddiggie]

wait two more weeks. Then try measure again.

+1 on that...

It's especially important to have reached a stable FG when you're going to be bottling the brews. I would let even a low OG batch go 2-3 weeks (or longer) before checking on it. Most of my batches have gone 4+ weeks in primary before going to bottle or keg.

I would advise taking the SG readings 2-3 days apart (one on Monday, the other on Wednesday/Thursday). Also remember to practice safe sanitation whenever you go into the brew post boil. Whatever goes into the batch must be sanitized first, or you run a very real chance of contaminating it. There's plenty of threads that post how to take a hydrometer sample on the quick so that you expose the brew for the shortest amount of time.

Once you have determined the batch has reached it's FG, taste the hydrometer sample. If it doesn't taste great, then give it more time before you bottle/keg it up.

Learn patience when brewing. Use time as your ally in getting great batches of beer to enjoy.

 

[MountainGoatBrewing]

Ok, ^ per your advice, I waited two days in between readings...both Sunday's and today's readings were 1.024. I am kind of pissed, b/c the OG was lower than expected, and this SG reading is higher than the expected FG.

Basically, if it's done fermenting, I'm going to end up with a 4.7% beer, when the recipe was saying it should be 6.3%!!!

It's been in the primary 10 days now - the first 5 were around 65, but it cooled off in the basement and has been hovering around 62º for the last few days. Do you guys think that could be playing a part in slowing down the fermentation and/or getting the FG down to where it should be (btw. 1.013-1.021)???

Other than that, beer tastes fine...maybe a very slight buttery vibe on the finish, but I can't really tell since it's not carbonated yet and don't have much experience tasting brews straight out of the primary or secondary.

 

[MountainGoatBrewing]

Should I bring it upstairs to 68º?

 

[Bigbeavk]

Yes take it upstairs and give it some time.

 

[unionrdr]

Bringing the temp up is always a good way to rouse the yeasties to get them going again. I had to do that on my Burton ale to knock off a couple more points. Keep the FV covered as well to keep out light & help the temp stay a bit more stable from night to day.

 

[daksin]

Keep that beer on the yeast. 1968 is SUPER SUPER flocculant. It's crazy. It will floc out at 70F if you look at it funny. 64F is the absolute minimum temperature for that yeast, I like the flavors you get by starting at 68 and raising it slowly up to about 72ish.

You need to rouse that yeast and get that sucker warmed up. Your yeasties are probably just asleep.

 

[MountainGoatBrewing]

Thanks a bunch for the info...I had a feeling things might have gone dormant, so to speak. I hope they wake up and get this Pale Ale to it's proper potential!

 

[MountainGoatBrewing]

Ok, it's now been at 70º for about 6 days.

It started off at 1.060 and the measurements so far have been:

1.0243 after 5 days at 65º
1.0243 after another 5 days at 62-65º
1.0235 after 3 days at 70º
1.0225 tonight after another 3 days of steady 70º

It seems like it's not really going to go down much further at this point, so we dry hopped, figuring another 5-7 days at 70º should do the trick.

Any feedback or suggestions would be greatly appreciated.

Also curious - having taken 4 samples after it went into the primary...I figure we lost about a bottle's worth of beer.

Does anyone have that Fermtech "The Thief"? It would be nice to put the sample back into the primary so as not to lose any beer at all. Although, I must say, tasting it as you go along isn't a bad thing.

 

[spenghali]

i have a thief, works great, can get a sample nice a quick with it to (hopefully) avoid contamination. anything you want to know about it?