The capacity doesn't account for the displacement of the filter in it so it's easy to overfill until you get used to it. If it's over filled or gets an air bubble in limestone filter, or too tight a fit under the limestone filter then it leaks all the water that can't get through over the sides. So it needs to sit on a towel, somewhere that can get wet. Having said all of that, I love it, the waters waters so tasty im drinking loads more. There's no plastic bottles to throw away so my conscience is cleaner, and I've cut down on sugar since I don't need juice to take the chlorine taste away.