If you plumb a sink by putting a water dispenser above it, the sink will have 250 units of clean water in it. If you remove the water dispenser, the sink will still have 250 units of water, and so will the water dispenser. You can use the water in the sink, and then just place the water dispenser back and refill the sink. The sink does seem to drop the erroneous water on log in or if one travels too far away from it.