I've been fermenting nonfat milk for a year or so now. I know the grains are supposed to grow in size the longer you ferment with them, but mine haven't changed as far as I can tell. I ferment a quart or two/month and haven't split the grains yet. Anybody else trying kefir?
Also, anybody try making kefir or yogurt with lactose-free milk? I got wildly different kefir with that compared to nonfat regular. It seemed to ferment and separate out to curds and whey quickly, which I guess I could expect since the glucose and galactose in it is more easily fermented by kefir microbes than lactose. It was also much more sour and alcoholic. I think I almost caught a buzz from my morning smoothie.