Definitely time to give them more milk to work with. Mine are in full kefir mode, and I have about a pint of buttermilk-like kefir every morning. The chickens are getting some, I am getting some, and the cats have been offered, but have so far refused . The grains themselves don't look like much; I am a little surprised that they still seem as though they are not fully re-hydrated - not quite as squishy as I would have thought. However they are doing their job, and I am doing mine (by drinking the stuff ). i find that by pouring off the finished kefir into a second jar (and capping that tightly), and leaving that at room temp (instead of in the 'fridge) I am getting a sort of second fermentation causing a slight fizziness, and it also isn't so cold that I can't face it on a chilly morning. I am not fond of super cold drinks, even in summer; definitely not in January.