Probably a dumb question....

I recently brewed an Oktoberfest, 7-26-09. I used Wyeast California Lager yeast. At the time I brewed it, I didn't have a lager setup, but when my A/C is running, my basement stays at a consistant 65 degrees. To me, this was pushing it, even though this yeast is good up to 68.

The first few days it was at around 72 until I turned the air on. Since then it's been constant. The airlock stopped bubbling about a week ago ( I know...don't trust it). I haven't opened it up because I'm almost positive it shouldn't be done yet.

Anyone have experience with this yeast strain? Is it a fast finisher because of the high temps?

Also, what should I do if it is finished? I'm assuming it needs a diacetyl rest at about 75 degrees, but does it need to be cold conditioned at 35 like normal lagers? I guess what's confusing me is the type of yeast I used. Do I use it like a lager yeast, or like an ale? This is my first lager attempt, so I'm just trying to sort out what I need to prepare for in the next few weeks as I let it sit (I won't be moving it for at least another two weeks).

Any comments are appreciated.

The fermentation is most likely done or very nearly done. I don't have experience with that specific yeast, but it's very reasonable for a beer to be done fermenting in a week or less. In general, higher temperatures produce faster fermentations.

If it is finished, then it's too late for a diacetyl rest, but I don't think this yeast even needs one. Warmer temperatures help the yeast clear up the diacetyl they produce. It is a lager yeast even though it ferments at higher temperatures than other lager yeasts.

Your beer will definitely benefit from lagering at ~34 deg. F. for a few months. It will clarify and some of the harsher tasting elements (if any) will fade away and you'll be left with a brilliantly clear, smooth, malty Oktoberfest.

In fact, all beers benefit from cold conditioning (lagering), even ones made with ale yeast.

-Steve