SOMEBODY'S not pulling their weight around here. Soap, I'm looking at you.
Next time you might want to try using something a little less absorbent. ~Not-So-Handy Andy
Metric water? Not in my country!
Submitter TurboJens explains this fix: The fill valve split in half and the floater does not cut off the water supply. The towel keeps the water inside and the wrench keeps it from overflowing.