First, the yeast I used was a washed Wyeast Munich Lager yeast. It has been in the fridge for one year. I used two jars to make my starter, and had about 3qt's of active bubbling starter that I added to my Beck's Dark clone recipe. It was very active for several days. I racked it after a week in the primary, which was around 55 - 65 degrees. There was almost no yeast cake.
I checked the SG when I racked it, and it was only around 1.030. It started at 1.040. I'm thinking WTF !!!! This thing was as active as a second beer I brewed the same day. That one had come down from 1.042 to 1.012. And that yeast was from two year old, washed American Ale yeast that I doubled up, and stepped up the starter over a few days.
I don't understand how it oculd be so active for the first three days, and now only have dropped 10 points. It is now in the secondary and in a swamp cooler to try and keep it in the low 50 degree range.
I will let it sit for a few days, then check it again. I might have to return the whole batch back into the primary, dose it again with active yeast, and this time keep it in the swamp cooler the whole time.
I'm wondering if that might be the problem.
This has never happened before, but then again, I haven't used such old washed yeast. Also it makes no sense because the other batch has fermented very well.
Oh well, let's see what you guys think.