Now, for some reason Nourishing Traditions always seems to have the "2 day" rule about letting things ferment on your counter. Maybe it's my house temp or our climate but 2 days never cuts it for me. Our kraut sits out on the counter for a good 2 weeks before it's ready. I let the beet kvass sit out a little too long and it started to develop a light scum on the top. I scraped all of that off, strained my beets and placed the tonic into the fridge. It's recommended that you drink one 4oz. class morning and night.
So try not to gag (I know, that doesn't sound very promising,) and drink it for your health!