If, on average, it takes you five minutes to brush your teeth, with an open tap, you'll spend something like 12 liters of water. If, however, you turn off the tap right after dampening your toothbrush and rinse your mouth with a glass of water, you'll manage to spend only half a liter. This saving of 11.5 liters multiplied by 30 days means a monthly saving of 345 liters of water. Have you seen how much can you save?