Product review (5 stars): Best price.
Just works as described! Best price... Yes, it foams if you try refill non-empty water container, but I assume they all do. What you will need is better measuring/dosing method as 'bottle cap' method is too messy. I just keep refilling an older generation Essick Air 1970 bottle that has a fancy no drip cap with dual chamber that does drain back into bottle.