I’ve designed this device to automatically fill hydroponics production pond with water. This device is using an Arduino micro-controller to activate a relay that will open/close an actuated ball-valve. There is 2 circuits per device. Each circuit got a low and high float sensors. When the 2 floats are in low position, the pond is getting filled. When the 2 floats return to high position then the ball-valve close. This 2 floats sensors avoid any short cycling. Plus, the micro-controller have a delay of 10 seconds before sending a signal to the relay.