I've been making sauerkraut for about six months now. I have two 10L Harsch crocks. Those work perfectly. I mix up cabbage, carrots, onions, celtic sea salt, and whey from raw milk kefir. I pound it with a wooden kraut pounder. I start filling the crock, having left some juice from the previous batch in place also. Then I put in some cucumbers, beets, turnips, radishes, garlic, ginger or whatever I was able to find for that batch. Then I cover those with the rest of the kraut. Turnips work the best, amazing flavor in the kraut. Leeks come out absolutely amazing. I normally get organic produce when possible. The leeks I just leave the roots on and it's interesting when it comes out the roots have grown about six inches.
Also I put in black peppercorns, white peppercorns, hawthorne berries, juniper berries, coriander, and a few other herbs.
In those Harsch crocks, after 4 weeks at 70F it is perfect, just slightly underdone and ready for a little more cool temperature aging. I can it up in quart jars and refrigerate to let it age a little more.