The air pump is acting like a siphon.....pulling air from the last waterfarm out and into the rez. So what basically happens then? That w/f is going to pull water from the next one and so on and so on all the way around the circle......until you come around to the first w/f which is going to pull it from the rez which is the normal way the system fills. . The pump is powering the pulling part.....gravity is handling the pushing part.

If you had everything daisy chained in a circle and took water out from one thing.....what would happen to the rest of them?