Originally Posted by Whiterabbit
I plan on catching my rain water into a funnel that goes to the barrel. Then I add a pingpong ball to the funnel, or any ball that is lightweight and hollow (floats) on the funnel. That should reduce loss from evap, but water spilling into the funnel will lift the ball then flow in.
That is definitely a creative idea. I agree a rain catcher is impractical in SoCal.