Version: 1.12.2-6.5.0
Forge: 14.23.5.2854

When you enable Sink Requires Water in the config and pump water into the sink and the supply of water stops (ex. pipe is broken) you can craft an unlimited number of recipes requiring water in survival and when you try and remove the water with a bucket it lowers the level of water in the sink and then when you try and empty the bucket the water disappears. (placing it in the world)