Constructing a Homebrew Atomix Air-Atomized Aeroponic System

The nozzle is a flat fan which is rotated axially at 120rpm but can go as fast as 3500rpm. The chamber dimensions/volume were geared to match the nozzle. The chamber is octagonal which is almost as good as a circle but still a pain in the arse to build compared to a square/rectangle. The nozzle is controlled by timer that fires up the rotation prior to the mist pulse and continues to rotate it after the mist pulse ends, ensuring the nozzle speed remains stable throughout the mist pulse. The nozzle height is adjustable and as the flat fan can be orientated horizontally, vertically or anywhere between the two, you have almost total control over the coverage. The mist itself is delivered in waves, so a 1 second mist pulse at 120rpm measured at any fixed point in the chamber will provide 2 passes of mist seperated by 0.5 second, increasing the nozzle rpm increases the number of passes and reduces the liquid delivered by each pass even though the total overall liquid delivered during the misting pulse remains the same.
With multiple nozzles, the origin of the mist is fixed, you`ll have overlapping mist patterns along with currents (air/mist) moving in different directions and speeds, aka, no hope of perfect control.
In a typical chamber (AA or HPA), some roots will always be closer to a fixed nozzle than others. Regardless where you put the nozzles, the roots actively try to seek them out (mist source). With this design they all have exactly the same distance to travel which is considerable even in a straight line that defies gravity. I`m optimistic they wont even attempt it as they`ll be too busy enjoying the mist thats arriving on their doorstep.
Here`s a nozzle rotation test i did to check the timer function, the (full cone PF) nozzle was a just stand-in for the one that will be used. No air was connected for the test but you`ll hear the solenoid click twice which signifies a 2 second mist pulse, the nozzle rotates for 2 seconds before/after the mist, then shuts down automatically and waits for the pause duration to expire.


Here`s the predicted (direct) mist coverage before it disperses. The total amount of liquid in the "doughnut" can be set as low as 0.27ml, about 1/20th of a teaspoon.

Here`s the chamber, not made of the most liquid friendly framing material but it`ll be ok for short term testing. If all goes to plan i`ll replace the frame with stainless steel.

Are you designing a commercial system here? This is rather complex for a hobby box. Is it made of plastic? Plastic would be pretty easy to shape and weld and using heat you can shape the bottom to drain where you want it to. How are you going to get the air to the nozzle body? You must be using some kind of swivel fittings. Is it hydraulically driven? Very, very interesting. Is that a Bete nozzle?

You must have made your own timer set-up for this. I'm still trying to understand the instructions for the Sestos B2E timer, they could have been written better. I have hopes of eventually using them to control different spray timing for day and night along with a multi-plex relay for multiple boxes. I believe AAA would support trees but I still have to learn not to dehydrate, poison, or kill anything first. I just decided to jump into "hydro" last November after the election. Things quickly changed directions multiple times to get to here. So much to learn, so little time.

Do you mix your own nutrients as well?

What is the white top made out of?

My first box was made with Hydro Farm premium 4 x 4 flood tray and the 4 x 4 lid for the regular flood tray. Good Quality stuff. The middle section I used 1.5 x 1.5" (2x2) for framing with a 2 x 4 on each corner glued and screwed together with 1/8" mahogany ply. The wood was all coated with SystemThree marine epoxy. On the inside surface I used 1/8" HDPE welded on the corners and screwed with marine sealant. On the top I used PVC 1.5" couplers for the plants. I made threads in the holes I drilled in the top for the couplers with a piece of 1 1/2" pipe nipple. I didn't have a tap so I improvised. I used weather stripping on the top and bottom of the middle section, which is insulated with foil covered foam insulation in the middle. No mist escapes the box unless I have the top raised to adjust or check things.

Its just a hobby but i like giving the boundaries a good shove where i can. If it was for commercial use / financial gain ,i`d just copy some 10 year old tag technology, tout it as cutting edge aero and add 3 zero`s to the price
I think that stand-in nozzle is a spraying systems, i have a few bete`s knocking around and some from other manufacturers but no delevans The timer is a modified off-the-shelf model, i replaced the mechanical relays with solid state versions which can last for years running constant 1sec on / 1sec off cycles.
There`s been quite a few hurdles to overcome to get this far, its all part of the fun and challenge. The rotation hardware and control was the hardest part to figure out, the air transfer wasnt too bad but it takes more than a swivel The chamber design is quite a bit different to normal, i`ve employed a free draining cone bottom with an air gap between the chamber floor and the run-off catchment, The idea is to air prune roots that hit the floor, forcing them to branch all the way back. Silkscreen has been used in sealed chambers to prevent roots sitting in the run off but no one has tried a root pruning air gap
A basic AA/HPA setup is complex enough for most people but this seemed to tick all the boxes for me and the only way to find out if it did was to build it.
I reckon this chamber could be suitable for 4 reasonable trees with a 1kw vertical light in the middle, if you leaned them out a bit I mix my own nutes, apart from making what you want, running drain to waste with commercial nutes can get expensive.

edit: the chamber top is made of hollow pvc soffit board, i`m picking up some butt-joint trim tomorrow to finish it off.

Liability could potentially be an issue selling a high pressure air and water system. Considering it is a very small group using high pressure compared to other ways of gardening that may be why Atomix didn't make it. Besides, most of those who would go with this type of system are most likely to build it too. I do admit it has it's challenges. It is hard on many levels when you jump right into air assisted from the git-go. Actually building it is the easy part. Figuring out how to adjust it, run it, feed it, get the plants to thrive, that's not as easy. It's all fun though.

One thing I learned about the Aquatec 5800 pump is that the pressure bleeds back down so that the pump cycles too often. It seemed to take a long time to reach the pressure of 120 psi the pump said was the pressure relief setting. I spoke with Aquatec and was told that the pressure relief setting wasn't an exact thing. It started bleeding before 120 psi and it had to work harder and pump longer to reach 120 psi. The tech said to adjust the pressure up with an allen wrench. That worked to reach the pressure faster but the pressure still dropped down to about 80 psi before it held. The fix was a simple check valve with a spring. The system held 125 psi for two days after that. I never had a problem with the pump cycling when the solenoids opened.

You're right about commercial nutes being expensive, more like a scam. I hope to figure out a good formula for a three part nutrient concentrate for drain to waste before I run out of the DM I have. Also a silica concentrate from potassium silicate. A pound costs about ten bucks. The silica concentrates start about twenty. Are you using one of Fatman's formulas? Have you used HydroBuddy?

HPA has been around in one form or another since the 50`s so its prolly more common than you might think. If you judge by whats posted on open forums, hardly anyone is using HPA and just a handful are using AA The simpliest way to run hpa is drain to waste, use the largest accumulator you can accomodate that will run the system for days on a single charge. Charge it manually and disconnect the pump when you`re done. Recirculating HPA costs more in hardware and filtering, its also more work with the daily ph/ec checks, top ups and ultimately dumping the res.
I like to use complicated hardware but keep the nutes simple. Some go the other way, simple hydro setup and 15 bottles of nutes/additives..go figure. Hydrobuddy is very useful but, imho, the earlier versions were a little better in functionality than the more recent ones. Angelfire is also useful.
Liability shouldnt be an issue if the air compressor is safe which most are. The lines running to the chamber will only be carrying maybe 40psi tops. High pressure liquid is safe, if something lets go you just have a flood to sort out. The price of the atomix was its main downfall, greed will always figure in a retail AA system. You can buy a retail AA for $2000 without a compressor, it uses a couple of aerolife nozzles (rebadged to Micro fog) which only put out 0-30um droplets so i wouldnt recommend anyone buy it. I havent kept track of what this new one has cost but i`d say the whole shebang could be built from the ground up for less than $600, a brand new bambi air compressor would add another $600.

It's kind of hard to see that HPA is any kind of common. But then all I have to judge it by is the forums as I don't know anyone here that even knows anything about it. Of course I don't know everybody.

I've tried to find nutrient salts locally. There are 3 hydro stores within 2 miles of me and another 8 miles away. They are popping up all over. Not one of those stores stocks much of anything for hp aero. None of them stock any salts other than magnesium sulfate, and that's for 5 times the Wal-Mart price. A few years back nutrient salts were stocked at one shop but when it got sold it turned into a bottled nutrient shop. When folks at the hydro shops are trying to sell me the latest and greatest new cure-all, be-all, wonder supplement with bio this and that they just look at me when I say I run sterile air assisted aero. Then say "Oh, we have an aero setup over here" as they show me some pots sitting above the reservoir with a few sprayers on a manifold. It's probably what I would have gone with had I stopped reading.

Have you found you had to change air and solution pressures as the roots thicken up?

I guess my nearest hydro shop is at least 20 miles away but they wouldnt stock anything i`d need. I bought the bulk of my chems from a local agricultural supply place, the major ones are all Yara brand in 25kg sacks. Krista mkp (mono potassium phosphate).krista mgs (mag sulphate),krista k-plus (potassium nitrate),krista sop (potassium sulphate) and calcinit (calcium nitrate). I bought a few kilo`s of mag nitrate (krista mag) along the way for some added flexibility. The trace elements were fairly easy to find in small quantities as was the iron, DTPA (11%), which comes in a 1kg box. I`m not keen on EDDHA as it turns everything pink

I guess the closest thing to air-assisted aero over here may be an amazon (LPA spinnerponic) with an airstone in the res. Once the mist is dialled in you shouldnt have to change the settings, just the timing.

I was thinking the same thing about the mag nitrate as an option but can't find any to have mailed. Guess it isn't essential. The farming in ak has gone to shit. The Delta barley farmers went tits up in the 90's and the dairy farms have almost all gone away so the farm supply stores are gone too.

Are you located east of Greenland?

Mag nitrate can be useful but its not essential. Its also very hygroscopic which makes airtight storage a must. No polar bears around here

Hi Atomizer

How's the octagon coming? I hope you post a video of the whirling mister in action inside of it.

Hi Joe
Its getting there but not quite up and running yet. I got sidetracked by a chamber temperature comparison test i did against one of the outdoor hpa chambers. With an unseasonally sunny day, the octagon ran 16.2F cooler than the hpa chamber so i`ve been busy revamping (aka ripping apart and rebuilding) one of the hpa`s to include the design features of the octagon. It`ll be interesting to see how it fares over the summer compared to the unmodded hpa chambers. I designed an automatic chamber cooling system for the octagon but it looks like i might need a heater for it instead.

That's interesting. What was the outdoor temperature at the time of the comparison? Were both chambers empty and in the sun?

I thought I'd already read all of the "my-true-hp-aero-plug-play-pods" thread but I hadn't. I am now! Very enlightening. It answers a number of questions and explains many of my observations as well. There is lots of homework to air atomized growing. Everyday I appreciate those who've shared pearls more and more. At least I'm not getting wet anymore.

The two chambers were side by side against a SE facing fence. Both chambers were empty with no mist running, i dowsed the interiors with a garden mist sprayer so they were wet. The external ambient air temperature was 77.4F and a tad over 90F in direct sun. The hpa chamber is fully insulated with 2" foil faced celotex (rigid PIR insulation board),and uses pool noodle pucks to hold the plants so its pretty well sealed.
The hpa chamber gradually heated up close to the ambient air temp. Insulation reduces heat loss as well as heat gain so, without any mist running, it can be a two edged sword.
The octagon has no insulation of any kind, the planting holes were fitted with 3" netpots filled with hydroton for the test. It uses over 32 sqft of breathable fabric to control temps, the fabric is exposed to external air but is shielded from direct sun and light. The spacing between the fabric and light shielding on the sides of the octagon create vertically orentated flat ducts that are open at the top and the bottom. Air flows up through the ducts, evaporating moisture from the outside surface of the fabric. In order to change phase from a liquid to a gas, the water needs to find roughly 1000btu per lb which it robs from the chamber interior, cooling it in the process.
The sides and floors of hpa/AA chambers are always damp and, unlike the great outdoors, most growrooms have 24/7 extraction running which can provide stable airflow.
The recently modified hpa chamber was getting down as low as 51F, it wasnt a particularly warm,sunny day for that test but it bodes well for summer heat.

You spoke of doing 4 trees in the octagon but how do you get past the dwarfing tendency

I'm not getting a picture in my mind of your fabric setup. Is the fabric located inside the box? How do you expel the heat taken up from the inside of the chamber? With nutrient laden atomized mist evaporating on fabric wouldn't there be a tendency for a buildup of salts on the fabric?

Dwarfing tendencies has more to do with genetics/grower than the method used.
The fabric is the box, the heat is expelled via the vertical air gap between the fabric box and the light shielding outer layer. The floor of the fabric box is cone bottomed, with another air gap (think of a horizontal air vent all around the base of the octagon) between that and the run-off catchment tray located below it. The entire fabric box is effectively suspended in mid air. The mist and roots are contained inside the box but external air is free to flow between the outside of the fabric box sides/ floor and the light shield/runoff catchment tray.
There may be some salt build up eventually but it would take a good while (months), especially when using low EC nutes.

How's the new chamber coming along? The more I look at it the more I like it. Lots of innovation there.

Which model Spray Systems nozzle is it that you used as the stand-in nozzle and how do you like it?

Its still sitting there waiting, always something more pressing on the to do list. I think the stand in nozzle is an su12 or 12A full cone pressure fed, cant rememeber which now but they worked reasonably well. These days i prefer to use flat fans but both have their up and down sides.

There are so many options with nozzles it seems rather mind boggling. You need to be an engineer just to wade through the catalogs and get what you need the first time. Why do you prefer flat fans and what is the down side of them? It seems to me the flat fan would be the one to use in your whirlybird chamber.

By the way, thanks for the tip on the Delavan # 8 nozzle. I finally got one installed last night. What a difference it made in the amount of mist in the chamber. There was still some rolling around in the chamber after three minutes. Tonight I'll replace the second one. Then it'll take tweaking the air and nutrient pressures to dial it in. But I think I like it in this big box.

The truth is you`ll never know if you have the ideal nozzle unless you test all of them. Most will work to some degree but they`ll work better if they`re somewhere in the ballpark to begin with. The ballpark range is quite wide thanks to the amount of control AA`s provide but there is a limit. You cant make a 200gph AA nozzle deliver 0.1gph and retain the same droplet range or vice versa. The flat fan pattern fits through narrow gaps better than a full cone, the downside is they use more air.