I am attempting to make sauerkraut this year from my abundance of cabbage for the second time. I tried once before when someone gave me a 15 lb head of cabbage but it spoiled on me before it got done. I didn't know that you had to skim it everyday then. This time I'm doing a smaller batch of 5 lbs. Funny thing is I don't really like sauerkraut by itself but I had an awesome sauerkraut salad at the Amana Colonies and decided that I would try to make some from scratch. Got some questions: 1) how long should it ferment before it's ready? Is it just a matter of taste or does it have to ferment for a certain time frame to make it suitable for canning? 2) When it's fermenting should it bubble so much that it pushes the weight out of the liquid and tries to bubble over the top of the crock? 3) Does it need to be tightly covered or left with air exposure for proper fermentation to happen? 4) Can I add more liquid to the crock over time?