I saved the yeast cake (about half of it) from a pilsner K & B and its sitting in a 1 gal jug with an airlock atm. It's the kit yeast from Coopers International Pilsner, which is rumoured to be saflager S189. I like this yeast because I can ferrment at the high end of lager range and it stays clean, also doesn't produce much of a sulferous odour (important as my bedroom is where I ferment )
I haven't played with yeast much and I'm wondering what the best course of action is. Should I wash it a few times with boiled/cooled water and then just pitch about half for my next batch? Am I better to use the yeast from the bottles than the yeast from the primary if I'm not pitching directly onto the cake?