Once cabbage is immersed in brine water, use a glass fermenting weight
to keep the cabbage down under the brine. If you do not have a fermenting weight, put a freezer bag filled with water or even stones on top of the cabbage. (I use 2 large bags, one inside the other so that if the bag breaks, it will not water down the cabbage into a tasteless mess.) The cabbage must be completely submerged.