_ GO AG and start harvesting yeast.
Here's a post from my blog
http://ioniaales.com/?p=9
"Anyone that has made some beer knows that a bunch of extra yeast is created, and generally thrown away. After you have fermented your beer and the yeast clumps together and falls to the bottom of the fermenter, a brewer can either pour fresh wort right on top of the “yeast cake†or the yeast cake can be collected in a sanitized mason jar or jug. In general, I believe yeast harvesting is easier for those using buckets for fermenters, rather than the glass carboys. Not only can you collect the yeast from the bottom of the bucket after transfering the beer to another vessel by using a measuring cup or anything similar, but you can remove the lid during fermentation and scoop the kreusen into a sterile/sanitized jar. I just did this with my second batch of 3787.
Since i didn’t have any DME (dried malt extract) to make a starter for my newly harvested yeast, I dunked an oldstyle can in sanitizer and poured the beer in with the yeast. The yeast will be very happy in the sterile, low alcohol beer and can last for months. Another of my strategies to make a single purchase of yeast last for quite a while was to brew a beer, ferment it out, transfer while making another beer, remove a fwe cups to a zip top baggie to save in the fridge for later. Pour fresh wort untop of remaining yeast in the fermenter. Generally, one should make darker beers on sucessive use, and increasingly bitter, or at least, shouldn’t do the opposite. If you can use it within the first 10 days or so you can just set the baggie out and let warm up a bit, then pitch the whole thing. Up to 6 months, and you should make a starter . In my experience. - I’ve limited buying yeast…
it’s helping to keep costs down, it adds up after 5+ batches. "