hey dankinx,
this should help you out for the design (its pretty automated after you fill up the reservoirs every so often on the right):
this picture is by rasta from "the edge" forum (on the overgrow site) 
and this is my 3d perception except i thought i could be smart and not have to include the smart valve, i was wrong. especially also by having the overflow pipe going into the top reservoir (which will cause all three buckets on the left to over flow), i don't understand fully about the air stones and thats why I haven't put them in my design yet, once i fully understand rasta's design then ill incorporate it into my future grow cabinet 
here is a picture of what my cabinet looks like. I am only going to have 4 bubblers in it, and the reservoirs will be outside of the cabinet.
I hope this helped you out dankinx. Does anyone have suggestions for: my DWC bubbler design, or my cabinet, or information about the pump and airstone used in the DWC bubbler. Because I also don't know if I'm supposed to have a air pump going into the grow buckets?
