Lager has stopped short.

[stevezx7r]

Hi all, I put a geordie lager kit together the other week and it's stopped fermenting at 3.6%. I calculated what it should have been - 4.5% and i'm now unsure as to why it stopped. Here's what I did. Mixed the kit with a kg of geordie beer enhancer and about 250gm of dextrose, I boiled this, cooled it then added it to the primary fermenter. As I wasn't sure what the weather (temps) were going to be I used a packet of saflager and a packet of safale plus a teaspoon of nutrient as insurance. I figured if the temps went too high for the lager yeast the ale yeast would kick in and if they stayed low then the lager yeast would do it's job. Either way I thought that both yeasts would be compatible (taste wise). Anyway, after 11 days I checked the gravity and it's at 1012 (SG of 1039 and FG should be 1005 according to the tin). I gave it a stir last night and it doesn't seem to have changed so i'm stuck (along with the fermentation) as to what to do. Would adding another packet of lager yeast bring it round or should I wait and see if the yeast wakes up again? Any help is much appreciated.

Steve.

[mysterio]

There is going to be a certain about of unfermentable sugar in the beer kit enhancer - if the instructions said just to add sugar then it would indicate a lower FG because sugar is almost completely fermentable. Also what temperature has the fermenter been at? Excessive swings in temperature can make the yeast stop short.

[prodigal2]

I would think that you have fermented down as far your kit will go. And 1,012 is a good place to be with mainly malt fermentables. I would leave it a couple of days and then, rack.

What was your fermentation temps out of interest?

[stevezx7r]

Thanks for that guys. The temps have been between 10C and 21C. Would adding more dextrose help? If so I would take a pint, boil it add some dextrose then put it back in the fermenter for a few days and check the gravity.

Cheers.

Edit, it tastes nice btw, just need more bang for my bucks.

[steve_flack]

The temps have been between 10C and 21C.

That's a bit of a wide range....

[stevezx7r]

Yeah, the temps were recorded using a kids thermometer (electric) it shows max/min/current temps so it could have been 10C most of the time shooting up to 21 when I opened the door of the shed on a hot day.