Previous comment from above:
The one negative thing about it is the awkward way you have to fill it. You have to remove the *tank* and turn it upside down to remove the stopper. But the thing is molded with curves everywhere so it doesn't set flat while you're trying to remove the stopper, fill the tank, or replace the stopper. Also the stopper is quite hard to remove and replace. I've discovered if I place it in the front of an open drawer, and close the drawer snugly while I remove the stopper, I can do it without the aid of another person. Also I use a jar opener to slowly remove the stopper.
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Ok, so try this. Slip your hand through the handle, flip it over...it is now in the palm of your hand, remove stopper, hold under tap, replace stopper, flip right-side up, replace in unit. The stopper removes with two fingers with no force at all as it is inset, no screw bands.Move it 1/2 inch counter clockwise and it drops out, literally, replace by reversing the process.