There's a simple solution, i'm looking for some pics i posted quite a while back....
I'll try building a word picture instead.... You have 2-5gal. buckets... each bucket has 2 holes in the sides at the bottom on opposite sides... All the holes are drilled 13/16 to fit a 1/2 grommet and barb fitting.. only three holes get a grommet and 1/2" barb... Now comes the fourth hole.... Here's where i need the picture [i know it's somewhere on this site]
Now we go to home depot, plumbing section, lawn fittings..... There is a 1/2" threaded cutoff riser, with 2 cutoff points.... cut off 2 sets of threads, set aside... In the white pvc section, find a 90* fitting with 1/2" female threads, to 3/4" slip....
You take the cut off riser, put a hose washer on it, put the threads left after cutting through the last hole and screw it into the 90* elbow with the 3/4" facing up.......... We're almost done.... Look around in the lawn plumbing..... you'll find a 1/2" barb with 1/2" male threads, that will screw into the 1/2" cut off riser....
We're left with one more part..... 3/4" thin wall pvc pipe used in low lawn irrigation systems.... We cut however long of a piece of the 3/4" pvc you need, then press it into the slip fitting.... This pipe will be higher than the water level in the grow bucket and the reservoir, which are the same....
The gh pumping column, w or wo the dripring, goes in the standing water column that is now filled with water from the reservoir... After the water is pumped out of the standing water column, gravity returns it to the reservoir.... Simple huh? I'll keep looking for the pics... This this was this was also done on a Waterfarm. The GH pumping column will move 6 gal an hour...