The final overflow rain barrel fix.

One of my overflow rain barrels is lower than the rest of my rain barrels and as a result it overflows.

The only solution I could come up with is to fill the barrel from the top with a float valve and empty the barrel from the bottom with a check valve.  I took care of installing the check valve a few weeks ago.  With that taken care if it was time to install another float valve

I decided to install it using a 1/2" FPTxFPT coupling.  I screwed the float valve into the coupling and then screwed the other end of the coupling to the brass overflow that I had installed on the rain barrel. 

I look at this now and realize that I could have removed the brass overflow and just screwed the float valve directly into the barrel.  Oh well, that can be a project for another time.  Until then, this will work.