I bought the large dispenser. I have to sanitize it before each fill because it smells of mildew.  I didn't clean once before refilling it and there was green scom growing on the bottom.

I use RO water that has been infrareded for sterilization----no tap water.

It is difficult to clean the inside.

IT IS NOT BPA FREE

They should make one where you can use the 3 or 2 1/2  gal BPA bottles you use to get RO water from the water machines outside supermarkets.