I have used mine milk kefir grains in grape juice and also sugar/dry fig solution for over six months now and almost always it is excellent outcome. It takes some time to get used to the process (time to culture/quantity of grains proportion). I add some organic dry ginger powder and a bit of cinnamon to spice it up and also to help digestion. The only thing is that I have to add some more grains from time to time since some get lost in the process.
Now with w.k.g. it is completely different outcome so I am wandering if they perhaps travelled too long and gone bad or else. I am going to keep on trying to revive them and I am hopping to succeed. Will keep you posted.