For those not aware, this is just dehydrated apple slices in water.
The yeast from the air lands on the water and starts to eat the sugars and fermentation begins. First it becomes alcohol and then it become vinegar.
The process should take around 30 days.
I put to many in and had to take some of the dehydrated apples out as they took up too much space once they rehydrated. I added extra water today to compensate.