Installing low flow faucet aerators is an inexpensive and simple way to conserve water. A faucet aerator is a device that screws onto the end of the faucet and mixes air into the water, so it reduces the flow of water while providing pressure. Aerators can reduce flow to as low as 0.5 gallons per minute (gpm). Most standard faucets are equipped with an aerator that flows at 2.2 gpm or higher. Regardless of what type of aerator you have, you should always turn off the water while lathering hands for washing, brushing teeth, shaving, etc.