Anyone that's still on the fence on this one should get off the fence, and had immediately to their local hardware/pet/hydro store with a shopping list cut and pasted from the first page of this thread.
We've done two so far, with six more coming, built exactly to spec down to the brand names for the air stones and valves. Once you get one done they go together really quick, we've been letting them run for a few days just to make sure they're water-tight, no leaks so far (the rubber o-rings seem like a simple thing but really are key).
They were supposed to wait a month or two while a soil grow finished, but impatience got the better of use so a 6" White Widow was transplanted from soil. Now, I was thinking this was a bit of a gamble, as excess dirt coming out of the root system may clog the plumbing. So when I took it out of the dirt I tapped off as much soil as possible, then gave it a thorough rinsing under the tape, then flushed it with distilled water. This left me with a mat of filthy looking roots, and I wasn't sure the whole idea was all that great anymore.
However, it was only one seedling, so I went ahead anyway and sort of spread the matted roots over a thin layer of pebbles in the bottom of the basket, added more pebbles, spread out more roots...you get the idea. After a few days of droopiness it sprung back up, and there is now some serious root development happening below. The water will be changed every few days until it no longer shows signs of dirt from the transplant. If growth continues to go as well as it has for this experiment, there could be a mass transplant in the near future for the rest of the crop. I'm now a converted bucket-head.
Note: made the mistake of using organic 'nutes meant for soil in the water, big mistake, caused a foam that prevented bubbles from breaking the surface which caused the roots to dry out...new 'nutes were acquired, all is now well.
Anyway, 10/10 on this design, I'll get some pics up shortly...
