A fountain can make a nice decorative fixture for your garden. But it isn’t always easy to run a power cord out to where you want it. So I decided to run it on solar power. The system is controlled by an Arduino. This allows you to save energy by programming when the fountain will be turned on. You can set up a timer so that it only turns on at certain times of the day. You can add a light sensor so that it will only turn on when the sun is shining. Or you can use the Arduino to monitor the battery’s voltage so that the fountain can turn itself off if the battery gets too low. You can program the fountain to react to a wide variety of conditions. You can do this for improved efficiency or just for fun.