The system is working really well right now and I am more than pleased with how the roots are doing. This new setup is by far the best I have come up with so far when it comes to getting fuzzy roots. So, I think it might be worth going over some of the key details for anyone who may want to try to duplicate it.
@GnomeyByNature mentioned before about someone coming up with a turnkey system someone could just buy and set up.
This is NOT that 
This is a 100% DIY, shade tree engineering on a super thin budget. Its not elegant, or pretty - but - it works Pretty much anyone should be able to duplicate it.
At the same time - this is not the only way to do it or the only good solution. As with pretty much any other part of growing out plants, there are a million different “best” ways to skin the cat. Also, my setup probably wouldnt work nearly as easily outdoors. I suspect you would need to go to extra lengths to keep the root chamber cooled down, and protect the electronics from outside weather, rain etc.
Here is an old drawing I did of the basic setup. The details have changed and I left out a lot of stuff, but this is the basic idea for indoor growing.
There are only two things about my grow tent that are even a little unusual.
- It sits up on my work bench.
- It has a 1" thick foam floor on top of the wood bench top inside the tent. That foam floor is mainly to keep heat from the grow space from getting down into the root chamber. Plus it is a lot easier to cut holes in 1" foam than 3/4" plywood
I cut a 24" diameter round hole in the wooden top of the work bench centered in the tent. Then I attached the stitched together grow bags to the wood top using wood screws. It needs to be fairly secure because a significant weight in roots can build up inside on the floor, but you dont need to go over board. The fabric is pretty tough.
Be sure to seal up all around the edges so there are no air or light leaks. Keep those two things in mind at all stages.
P.S. remove all helpful kittens before you turn on the nozzles for the first time!
The nozzles Im using now are the brass and stainless Delavan 30609-8. I went cheap and made my own adapters for the air fittings.
A short piece of 3/8" push fit tubing will slide over the water fitting end and the O-ring just perfect. You could easily use 3/8" for the air line too.
This is an early version of how I set up two nozzles in the bottom. The nozzles can pivot up/down and you can turn the PVC pipe to change the angle from side to side.
In the newest version, the nozzles are fixed at about a 45 deg angle as far as up/down, but I can still turn the PVC pipe from side to side.
I use a heat gun to soften up about a 2" long end section of a piece of 3/4" PVC pipe, then press it flat on the work bench or in a vice. Hold the rest of the pipe at the angle you want while it cools. Then drill some holes and zip tie the nozzle in place.
In this new version, I run the 3/4" PVC pipes all the way up and through the foam floor - which is also now the ceiling of the root chamber. I run the air lines inside that pipe so they stick out at the top. The solenoid attaches close to the pipe, then the air lines run to the regulator which is just outside the tent.
Seal up the top of the PVC pipe and all around any openings, etc - remember - no light or air leaks!!
Also, be sure your tubing is opaque or cover it with aluminum foil to keep light out. If you dont, algae might grow on the inside due to moisture in the air lines. Those cheap water traps do not keep out all moisture.
The siphon tank is that cut down carnation dairy creamer container in the pic above. The float valve fits inside. Drill holes for the water lines that are a tad small, then force the tubing in and seal up with hot glue inside and out. I sand all around the openings and the tubing with coarse sandpaper to help the glue bond. I have had no leaks yet in almost 2 years.
As you can see, the nozzles are in the bottom shooting up at roughly a 45 deg angle.
When the babies are first put in the system, I point both nozzles toward the center of the chamber. This maximizes the amount of mist directly hitting the net pots. You want to keep them extra wet at first to help them get over the transplant shock. I also crank up the flow rate until the baby roots stay covered in lot of droplets. I keep it that way until they start to grow again. That usually only takes maybe 2 to 3 days at most.
Watch your flow rates. mist quality and density all through this time. While you are flooding the chamber is a good time to see how it looks - just dont dry out the roots while playing around.
Once the roots start growing, I lowering the flow rate gradually until I start seeing fuzzy hairs. I also start to turn the nozzles so they point more to the side are not hitting the roots as directly. I turn them both so they create a rotation in the mist causing it to swirl in a circular motion around the chamber. This is when you really need to start looking at hang times and watching the roots closely to be sure they stay in the Goldilocks zone of just right wetness
All of these changes should be done in small steps, while you look at the roots every few hours. Make a small change in timing or nozzle position, then wait 3 or 4 hours and see how it looks. I take lots of pics to I can do before/after comparisons. Changes can happen very fast as I outlined earlier. If you keep a close eye on things, you can get it dialed in over maybe a day or two at most.
If you screw up and the roots get damaged, dont stress too much. The plants can recover from an amazing amount of damage. Trust me on this one. I have stress tested many babies LOL!!!
About the only other thing is my rez. Its an old, very thick plastic icechest. It holds maybe 12 gallons max, but I rarely go over 8 gallons unless Im going to be away for several days. I use 2 liter frozen bottles of water too keep it cool. I also have an aquarium pump inside the rez to circulate and mix the water when I do refills.
I think thats about it… oh - 200 mesh filters on the air and water lines.
oh - here is the latest root pic.
EDIT: Added a couple of pics above that I forgot.
Just cut the bottom out of one of them - save that piece for hatch covers, etc - cut off any handles, then hot glue them together to get the height you want. In my case, 2ea 30 gal bags ended up at 55 gallons total.
