FG too low

[cc986]

I brewed Greg Hughes's abbey beer last week but wanted it slightly stronger than 6.4% so I added 325g of Belgian candi sugar which Brewfather said would take the ABV to 6.8%, which was about what I wanted.
On the brew day I hit the OG as per Brewfather (1.064) and final volume (23litres).
For fermentation I used two packets of Wyeast Labs 1214 Belgian Abbey style yeast and fermented at 22 degrees.
The FG according to Brewfather should have been 1.012, but after 7 days in the fermenter it is 1.000 and has been for the last two days. This means the ABV is much higher than I had wanted and I'd like to try and understand what has happened and if it is going to be a problem.

What should I do now - transfer to a secondary fermenter and store at a lower temperature for a few weeks before bottling, or leave it in the primary for a while longer?

[Rookie]

What is the recipe?
Are you sure about that F G? Hydrometer or refractometer?
Something is off, no way it should be 1.000.

[cc986]

Hydrometer. I've checked it twice, yesterday and today. It does taste like a very strong beer as well. Its a nice taste but it has that heat as it goes down the throat that strong beers have.
I do have a refractometer as well but I normally only use a hydrometer once the fermentation has started because I'm sure I read somewhere that refractometers are not accurate once the fermentation has started. I'm still relatively new to this though, so if that is not the case I'd be happy to hear that.
The only other thing I would say about the beer is it is a bit cloudier than I normally see after 7 days.
The recipe is Belgian pilsner, vienna and biscuit malts.

[Jocky]

That yeast is listed as attenuating 74-78% and has a 12% ABV alcohol tolerance, so it's going to attenuate quite a long way. 1.012 as a FG would seem way to high for a Belgian yeast with a decent dose of sugar in there too. I'd be expecting it to finish 1.005 or so, but I'm not surprised to hear it go lower than that.

Give it time and the alcohol will smooth out a bit. I would leave it in the current fermenter for another week warm, then bottle it and let it age for a few months.

[McMullan]

I’d ignore what Brewfather predicts. Some yeast strains are more predictable than others. Yeast suppliers’ performance data are based on limited lab conditions, which don’t cover every potential home-brew scenario. All Brewfather’s ever going to do is lift the data. Like Jocky typed, with strains that have a high stress tolerance the outcome can be more variable than the suppliers’ data suggest. Although it's unusual to get complete attenuation of home-brew worts. It looks as though you’ve managed to optimise fermentation for attenuation, for some reason. I’m guessing you mashed at a low temperature to produce a highly fermentable wort then fermented at a relatively high temperature. Depending on how you control fermentation temperature, it might have been a lot higher than 22℃. (Best way is to measure the actual wort temperature, using a thermowell in the FV.) Complete attenuation of home-brew beer worts is not typical, but nor is it the end of the world. ‘Worst case’ is you’ve got a stronger beer than expected.

[cc986]

Thanks for the advice everyone.
I just checked the gravity with a refractometer and it was 1.032 which is clearly not right, so I think that confirms that they are not suitable for after fermenting has started.
I checked the yeast profile in Brewfather as well and it is set correctly, so it looks like it hasn't done a very good job of taking into account the fact that the yeast can go to 12% and it would use up some or all of that extra candi sugar.
McMullan.. mash was 65 degrees. I have a fermentation chamber and set the controller at 21 degrees. There is a stick-on thermometer on the side of the fermenter which showed 22 degrees throughout, but I've no idea how accurate they are. I've not heard of thermowells before so I'll have a look at getting one of those.
I guess a lot of this is down to experience because no matter what Brewfather says in the future I won't be putting 325g of sugar in a brew to raise the ABV by 0.4!
One last question please. When I bottle a beer at that strength do I need to prime or will it condition without?

[Jocky]

Prime it. Belgian ales are supposed to be well carbonated.

[cc986]

Thanks Jocky.

[McMullan]

I checked the yeast profile in Brewfather as well and it is set correctly, so it looks like it hasn't done a very good job of taking into account the fact that the yeast can go to 12% and it would use up some or all of that extra candi sugar.

There is no correct setting to pre-input in any off-the-shelf brewing software. Not for all yeast strains. Again, all Brewfather can do is lift the yeast suppliers’ limited data. What you can do is assess it empirically yourself using your own procedures and equipment in your fermentation environment. Then edit the attenuation value according to your observations. But first you have to be confident your procedures are working and you can monitor them reasonably well. I’m not sure about Brewfather, but I can do this quite easily in my favoured software, BeerSmith3, a package designed and managed by people who understand the brewing process, not chancers lifting data and plagiarising like parasites just because they can design a fancy interface. I’m not a fan of cloud based services either. I prefer to be able to use a downloaded package for security and privacy reasons and for when I need to work offline. BeerSmith3 has both options

Also, don’t blame the small sugar addition in this brew. A decent Belgian or English ale can be transformed by adding sugar. Some of the finest beers in the world can’t be wrong, right?