Even though I demostrated only the situation of adding cooler water to a container in warm weather, the other possibilities are endless. The code for the arduino can be altered to add only a certain amount via how far to tip the cup as well as how often to 'update' the bosy of water. Although this seems silly, the use for a cheap and easy way to control water temperature is needed. To keep a small pot of boiling or cold water nearby that could contribute to a body of water as a whole can be simply done. There is no human interaction required for the actual distribution of water.