Step 7: Program It, Use It
Every 12 hours, it checks the water level using the ultrasonic sensor. If it is fine, it will flash a green light and go to 'sleep' for 12 more hours. If not, it will add water, reading the sensor as it goes, and when it is at the desired level, it shuts off and goes back to sleep. If a long time goes by and it senses that the water level has not risen, it will flash an orange light indicating an error, sleep for 5 minutes, and repeat the process all over again until you notice and solve the problem. It could be that:
1) The reservoir is empty
2) Something is wrong with the motor/circuit
3) The tank is completely empty for some bizarre reason
This feature will protect the pump from filling the tank until it overflows (if the reservoir is big enough/has enough water in it to do so).
Lastly, and definitely not least, put the solar panel in a good location. If you were wondering about the image comment in step 5, I have a sun roof in that room, which is ideal for my solar panel. You can't see it in any of the pictures, but it sits on top of my fridge to gather the light to charge the battery (very very slowly, but surely). The solar panel and batter should keep the setup self-sufficient (except for the reservoir refills)....
Here's a video of it in testing: