I have a schwarzbier and a a black IPA both made from the same wort (O.G. 1.055, Black IPA raised up to 1.062 by steeping crystal malt). The schwarz was fermented with the dry Weihenstephan strain, and the BIPA with Nottingham.
Both beers are now stuck between 1.020 and 1.021 after 21 days each. The schwarz was removed from my chest freezer to start a diacetyl rest, but never moved any further. I roused the yeast by shaking the keg in which is was fermenting (figuring there is no oxygen in there). This was a couple days ago, and I am waiting another few days before I check it. I just checked the BIPA, and it has not moved in a week.
Any ideas here? I figure the first answers would be that my wort was not as fermentable as I thought it was. It was mashed at 150 for 90 minutes. Next I figure my thermometer may be off, but I am pretty sure that is not the case either ( I just checked it against another for good measure ).
I was planning on racking the schawarz onto the Nottingham when it finished, but now that it is not moving either, I am really at a loss. Any explanations other than the ones above would really help me cope here.