so basically i make a square of pvc pipe and filled it with these porius rocks so my roots got something to grip to and drilled 20 holes in the square 5 plants for each pipe. i then put my clones in the holes and run water with nutrients through the pipe twice a day and let my girls feed for like 30 minutes. the only problems i have is lighting i need some sort of lighting system that wont cost me an arm and a leg and a good chemical ratio. Obviously i have yet to build this but if anyone sees any problems with my design please let me know before i get in to deep.
You should look at budslinger's recirculating bubble buckets in diy if you ask me. So simple and efficient it's scary and comes cheap too.