Combining tanks with AWC setup?

[Schulks]

I have a 70g tank with a hydros system that has an AWC setup. I am setting up a 22g cube on the other side of the room and I was thinking about moving the drain and fill line to the 22g cube and using my AWC to sort of combine the systems. I could just run the same AWC program and it should just fill above the ATO in the 22g cube then drain back to it. Am I crazy? Yes?

 

[Reefing Madness]