Automatic water-filler for solar fountain WIP

I made a solar fountain for my deck one year ago, but it keeps running dry as the water evaporates. This my WIP to build a automated filling system for the fountain. It will be plumbed into the garden drip system, so it will fill during the time the sprinklers/drip feed runs. Basically inside the tube is a table tennis ball. As water rise the ball floats and shuts off the flow. This way the fountain should get topped up as needed.

This thing was made with Tinkercad. Edit it online https://tinkercad.com/things/afJaXz9ZcRJ