Post fermentation

Oh hai!
So I did my first yeast starter on my latest brew, which was Friday (an authentic Bavarian hefe) and I was wondering #1 how long will it take to ferment approximately, and #2 is the cake on top and in the bottom yeast I can recycle and use again later?
Prost!

#1 Assuming its about average gravity for a hefe (1.05ish), 2-3 weeks should be fine. It should probably be done fermenting in a week or less depending on the temp you've got it at, but I always like to give it a little extra time to improve. 3 weeks is probably about what I usually give, unless I want to free up a primary in which case 2 weeks should do you fine in a pinch.

#2 Yup, take a look at the yeast washing page and go to town! As long as you keep everything sterile, you could reuse all of that yeast. If you give it a bit all of the yeast from the top will eventually settle to the bottom where you can get at it after you rack the beer off. I suppose you could scrape the top (krausening I believe?) and toss into a new batch if you wanted to, but I'd check around on here to see if there are any things to watch for from someone that's done it.

#1 3 weeks would see it really good, I was in a rush for my hefe, I had some really hungry yeast and they were done eating in 30hrs flat 1.052 t0 1.012 however that is really unusual. Typical ferments held at the correct temp with the correct pitch rate with the correct O2 etc etc can finish in around 4-7 days. Then you want x2 that for clean up (aka secondary fermentation).

#2 I Slant rather than wash but from what I have read a pressure cooker is the best thing you can buy for either. To be able to guarantee that the water you are using is 100% sterile is a good thing. If your not comfortable with sanitation I would leave taking the yeast from the krausen to a time when you are more experienced. Just wait for the cake to develop and plan your bottling/transfer to secondary so you can maintain a sanitary work environment.

Clem