Hah, I’ve seen that home assistant video with the guy using a magnet spinner to keep his nutes stirred, that’s what I was planning on doing one day…
So do you like the Home Assistant?
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Nice stuff! Ive looked at most of the things you listed, but hadnt seen those particular solenoids. You have to look closely at the specs to be sure the orifice sizes are not too small, but they look very nice - and $$ for me.
I agree about the cheap solenoids being difficult to disconnect the tubing. I use a wrench to hold the release collar in while pulling the tubing out, but it can still be a chore.
Unfortunately, my budget wont allow for those nicer solenoids or much in the way of automation.
Tell us more about your growing room setup. Im particularly interested in your root chamber, how you control chamber temps, number and placement of nozzles, timing settings, flow rates, number of plants, drain to waste or recirculating etc.
Oh - do you grow cannabis or something else?
The fuzzy roots in question when they are exposed to certain pressure from the water, don’t even remember the number, they definitely transform into smooth, your microscope is not lying to you @anon32470837! It takes quite a while of huge humidity and no direct water contact to change back to fuzzy. The fuzzy roots are really strange looking under high resolution optics, they are like randomly little hairs growing in random directions. Welcome back!
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ok I made you these photos for your root porn collection larry, I know they get your motor running!
oh yah, also it proves the difference between the humidity root and the water root.
300x magnification darkfield.
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I don’t grow pot. I’m all in veggies - mainly cucumbers, red bell peppers and variety of herbs. I used to grow a lot of lettuce at some point, but I stooped as we cant manage to eat it all 
Root chambers: I used to have 2 cucumber plants per 27 gal container from CostCo.
But its to small for 2 plants as the root mass that the cucumber plant builds up over its life cycle is insane. At some point it fills up the entire container and the plant slows down its growth. 1 plant per container is ok.
I managed to get pretty good results - like over 30 lbs of cucumbers per plant in less than 2 months of grow cycle.
Since I have mini split ac now, I dont think I need to control the temp inside the containers. They are all wrapped in Reflectix insulation. During the day cycle I keep 74 Degrees in the room and 67 during night. If the temps inside the root chamber are an issue, one could slowly pump in filtered cold air from outside the room - I have automation for that.
Inside the grow room I have only the lights, oscillating fan and defumidifier - everything else that generates heat like led light driver, air pump, controllers etc is placed outside.
I used a system like this one. That was all before I got hooked to HPA/AAA.
I’m now switching to 67 gal one: link
For the bell peppers I want to use this setup:
Plants in bot sides of the lid - 3 or 4 on each side.
1 AAA nozzle (if I find such that is working) on one of the sides of the container that sprays along the longs side in the middle.
or
2 HPA nozzles(netafim or afd) on each side.
I want to live the middle unobstructed as much as possible and have the plants on the side to leave room for the nozzle to spray normally.
HPA Design
AAA Design with syphon fed nozzle:
@anon32470837, thx for sharing the delavan nozzle. Does it have Stainless Steel internal parts and only brass shell? I would avoid using any brass (any material that has copper) as nutrients pushes ions out of the metal that could case poisoning in plants. I’m very careful with the materials I use as I eat what I produce. Containers, fittings, tubing, nozzles I use are from pete plastic or such that cant cause harm.
My Grow Room Setup:
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Awesome photos - thanks!!
Where did you get the info on the water pressure causing changes in the hairs? id like to follow up on that as it may have a bearing on my current experiments.
Awesome grow room! I wish I had the space, and the budget to do something like that.
I would love to grow some vegies. That would make my wife a lot happier 
Oh boy - I hope you dont mind getting the third degree. I have a bunch of questions!
Keep in mind Im approaching this from a fuzzy hair point of view.
If you were not getting any root rot, then your water temps must not have been out of line. Do you run sterile rez or beneficial bacteria or anything like that?
Have you grown any plants yet with the HPA nozzles or are you still in the testing stages? One comment on your setup is maybe dont get the plants too close to the sides. In my grows, Ive found that when the roots are too close to the sides of the chamber, the part nearest the sides doesnt get sufficient mist and tends to air prune and/or stray smooth unless you are over misting the rest of the roots.
Im also going to suggest you use at least two nozzles - one on each end firing toward the center - or you may end up with uneven coverage. Keep in mind, I am still thinking more in terms of root development rather than plant yields.
I just went back and looked through my HPA thread. The grey Hypro’s I used had horrible hang times and produced very few fuzzy hairs. When I changed over to the stainless HPA nozzles, I got tons of fuzzies - see the first pic in post 1. The nozzles I was using - link above - worked really well - BUT - I had three of them in the chamber early on. I added at least one more late grow to help even out places where the roots had blocked mist flow.
I really think you are going to need more HPA nozzles if you want fuzzy roots.
Your 67 gallon chamber is not that much larger than mine - 55 gallons. So far, the best flow rate for me getting fuzzy roots has been around 4 liters/day plus or minus maybe 15%. I think the best timing back then with three nozzles was around 0.7 seconds ON time x 60 seconds or so OFF time - depending on pressure settings.
I dont think you will be able to evenly fill a 67 gal chamber with a single nozzle in a way that will give you fuzzy roots - at least not everywhere.
That same over all flow rate - ± 4 LPD - has worked well for the AA setup too. The Delavans nozzles have similar flow rates to those HPA nozzles, so the timings have also worked out in the same ball park, but with somewhat longer OFF times - due to better hang times. Its generally been around that same 0.7 seconds up to 1.4 seconds depending on the number of nozzles, where they were placed, and pressures used. Off times have been from maybe 70 seconds up to 90 seconds.
One of atomizers “rules” is you need good even coverage first, then you look at flow rates and set timings to stay within his ranges. My tests seem to confirm most of his numbers.
The problem for many root chambers is by the time you get enough nozzles to get good even coverage everywhere, your over all flow rate is too hi to get fuzzy hairs because if you try to run at really short ON times, the run-on drips and slop in solenoid function makes for a lot of waste and poor droplet size uniformity - you end up with too many big drops and not enough micro drops. So for most folks, its a matter of balancing coverage vrs flow rates.
For your chamber I suspect you will need at least 4 HPA nozzles - two on each long side. You might get by with 2 Delavans - one on each short end, but Thats going to leave areas with uneven mist coverage, and require longer On times. I think again you will be better off with three or four spread out on the long sides. Your chamber is radically different in shape from mine, so I may be way off. You will have to try different options to see what works best.
Ive found that the math can only get you in the ball park - if you are lucky. It can throw you way off unless you measure actual flow rates AND have reasonable hang times.
In the end, the only way to know what works is to watch the roots closely and adjust timing settings, flow rates, etc until you see fuzzy hairs - or dont as is my current status with my newest changes.
Sheesh - I got side tracked giving you unasked for advice and forgot to ask more questions…
So what timing setting have you been using and whats worked best with which nozzles?
Interesting idea using your air compressor to drive a pressurized rez rather than one of those aquatec pumps. Have you tried this yet? One problem I ran into was when I had air trapped in my accumulator tank. I was running 100-120 PSI in the tank and that air caused major problems. The main one was that that hi pressure air increased the dissolved C02 in the water. That did two things. It drove the PH down drastically, and it caused fizzing in the water when the pressure dropped again - just like in soda when you pop the top. The PH issue was a real pain. Running at lower pressures, you may not have that issue, but you might want to check the PH as the water leaves the nozzles to see if its still within range.
The AA setup looks good other than what I said above - I think you will need more nozzles - maybe.
These have an SS insert, but the water passage is brass at the inlet. I have not been concerned about that because the water only has a very short time in contact with the brass, and over a small area. Plus, Im running fairly low EC levels, so there will be less leaching. If it was a solenoid where the water sat in a brass fitting 24/7, I would be more worried. I doubt you could measure the copper level in the water as it left the nozzle.
But - if your are concerned, they make an all SS version for about 4 times the cost - $25 vrs $110 or so on Ebay. Look for the 30610-6 version. Unless you want to make your own DIY adapters like I did, you will also want the part number 29713-2 SS adapter. Ive attached the Delavan catalogue.
Delavan-SN.pdf (510.2 KB)
Ok, thats enough of me spouting off - for now 
LOL as you can see I have no problem with looooong posts!
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Side note here on my current experiments - which are not working out as I hoped as far as fuzzy hairs.
For quite some time I have had the feeling like things might work better if I had a lower VMD = smaller droplets. Several things lead me in that direction.
- Ive seen fog-ponics grows using ultra sonic misters that actually produced some nice fuzzy hairs - for a while. Those misters have other serious issues that I dont like, but they seem able to make fuzzies even though the droplet size is sub 5 micron or way too small according to atom
. - In looking at some of atomizers videos, his hang times were a lot longer than I was getting with the delavans. His OFF times between roughly .5 second ON cycles, were in the 90 second range, and there was still a good deal of mist in the chamber. That indicates there were droplets hanging around that were in the 10 micron range and smaller.
He has said several times that you want droplets between 5 and 80 microns, so that fits. The problem for us is that there is no way for us to know for sure what droplet sizes we are getting. All we can do is measure the hang time and calculate what the SMALLEST droplets that are left in the chamber based on that hang time.
These two charts tells how fast droplets fall in still air.
I also was going off of a research paper @heathen found that covered some smaller flow rate Delavan nozzles. The key take away from it for me was that the droplet size varies based on the Air to Liquid mass ratio or ALR. Its not the relative pressures, its the mass of air vrs the mass of water leaving the nozzles.
EffectofAtomizingAirFlowonSprayAtomizationofanInternalMixTwin-fluidAtomizer_Chong.pdf (501.4 KB)
Anyway, all that led me to decide to experiment with higher ALR’s to try to get smaller droplets on average - lower VMD.
So far, its not working very well at all. I started with the Spraying Systems SU2 siphon feed nozzles and got zero fuzzies. I think at least part of the problem is they have too long a throw distance for my small chamber - even at the lowest air pressures I tried.
Now Im back to the tried and proven delavans. Ive been running them at much higher pressures and much higher siphon heights than I did in the past.
Before I was running them at a max 0.5" to 1" siphon height and air pressures from 7 to maybe 10 PSI worked well. Now Ive been up to 4" siphon height and 30 PSI. Thats giving me much longer hang times - up to 3 minutes.
Ive been playing with the new settings for over a month now on two different sets of seeds with zero fuzzy hairs.
BUT - I just last week discovered that my nozzles have become partially clogged in the air passages. This could be due to corrosion of the brass where it is close to the stainless or it could be debris that has become stuck in there. The water passages on these nozzles are very large, and would be impossible to clog easily. Plus I can see right through the water path. The air passages on the other hand are much tighter clearances.
The net result is that the three nozzles I am using have very different water and air flow rates.
So, Im now running the nozzles back at the original settings that produced fuzzy hairs and I have ordered three new nozzles. They will be hear next week some time - just in time for me to start some new babies in the chamber of death…
Which reminds me - one other possibility for the lack of fuzzies is the seeds Ive been using. Ive been using seeds that have not worked out well for me in the past - lots of issues, mutants, slow growth etc. I doubt this is all of the problem though. I did get fuzzies with these seeds on my last grow.
Now for more waiting…
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I almost forgot about this. The reason Im interested in reading more on water pressure vrs fuzzy hairs is that all of my recent failed experimenting has involved higher air pressures and/or narrower cone angles. The net result is water leaving the nozzles with more speed and hitting with more force.
The Spraying system nozzles have a cone angle of around 18 deg and a throw distance of up to 18 feet. the delavans have a cone angle from 30 - 65 deg depending on pressures and a much shorter throw distance. The cone angle goes down as pressure goes up and the throw distance increases with air pressure.
Wider cone angles, matched with lower air pressures means less force on impact.
As a contrast, the HPA nozzles I used had a cone angle more like 80 deg and very short throw distances even at 80-100 PSI.
So, Im now wondering if this might be a factor in my lack of fuzzy roots.
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unfortunately that information was from the original overgrow. On the other hand all the studies on root hairs just say they form in “moist air” I was using 90% RH for that. Gotta be more specific info around though. I’ll read some shit. Interesting side note, they claim the root hairs “absorb” things. Except… you can see those smooth roots from the DWC have no hairs, so the absorption must be through something else like the root epidermis cells. I think the epidermis forms the root hair, so it makes sense.
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It was my understanding the hairs were not really that different. It was mainly a matter of more root surface area, plus more efficiency, so effectively having more roots when you have hairs. However, that is just anecdotal comments from other root nerds. Ive never seen any studies on root hairs. Gonna have to look
LOL Google is amazing some times. I googled “root hairs” and got this as one result.
Smoke molecules cause root hairs to grow
To check their hypothesis, the team of researchers exposed young arabidopsis plants to the karrikin molecules as they occur in smoke. This indeed significantly increased the growth of root hairs.
Im not sure how this helps anything we do but it sure is interesting! Maybe I need to buy a carton of Marlboro cigarets and see how it goes…
There are tons of results for “root hairs” and Ive only begun to search, but this one caught my eye. Lots of very interesting information about roots and light. It looks to me like light by itself isnt really all that harmful to roots. In fact, several plants roots seem to develop MORE hairs in the presence of light!
Development of root hairs.pdf (1.8 MB)
Still reading and looking but nothing - so far - about pressure being a factor.
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Damn I have some reading and catching up to do, that was fast 
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I love some good root porn and info.
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I must have read 100 different publications. They all refer to the “root hair” as absorbing water and minerals through passive and active transport. On the other hand, now I am a plant physiology expert lol! The weird part is the smooth roots are an adaptation for aquatic plants, where the roots don’t need to support the plant and there is water everywhere.
https://plantcellbiology.masters.grkraj.org/html/Plant_Cellular_Physiology2-Absorption_Of_Water.htm
this was the most detailed and outta sight article I read. LOL unfortunately it doesn’t contain the answers we are looking for. sigh I guess it’s time to start gathering observations.
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I can’t help myself but there was another article I had read online that was…so good!
https://www.nature.com/scitable/knowledge/library/water-uptake-and-transport-in-vascular-plants-103016037/
I read this one a couple of times, lovin’ it!
combine that article with the first one and you’ll be 7th level root master.
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ok for what it’s worth, they say the roots exude ethylene to promote root hair formation. When there is some actual water that runs over the root it washes away the surface ethylene, resulting in the inhibited root hair growth. I suppose that means there can’t be enough moisture around to cause a drip to form or else the roots will be smooth.
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[quote=“JoeCrowe, post:30, topic:36453”]ok for what it’s worth, they say the roots exude ethylene to promote root hair formation. When there is some actual water that runs over the root it washes away the surface ethylene, resulting in the inhibited root hair growth.
I suppose that means there can’t be enough moisture around to cause a drip to form or else the roots will be smooth.
[/quote]
That pretty well sums up the balancing act when you grow with HPA or AA.
That is not easy to do sometimes. First - you need more than just a humid grow space. There has to be enough actual droplets of water collecting on the root hairs to keep them alive. If you just have humid air, they “air prune”.
See in these pics how parts of the root mass are nice and white and fuzzy, but other places the roots are shriveled and browning?
This happens when you have uneven mist distribution in the chamber. Some places get the correct amount and size of droplets, while other places get too little - or too much. This is one of the things Im trying to make better with this latest set of changes.
Up until today, its looking like I am delivering too much mist to get any hairs - or too much pressure?
Yesterday, I lowered the air pressure down to 7 PSI and reduced the siphon height back to 1", and tonight I finally see some fuzzy hairs! Not much but its a lot better than zero
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I haven’t read that article, but what do you think would happen if you put a UV light in your chamber? I would imagine it would kill any algae but also probably all bacteria good and bad… they also make some UV lights that produce ozone and I’m not sure if that would be good or bad and if it’s bad, you can get some that don’t make ozone.
Maybe, as you said, short throw is key because maybe what we should be after is actually the turbulent part of the spray?
Sterile rez.
Still in experiment phase. Thx for the advise - much appreciated.
Below might be a way better solution:
That is a very good point. I haven’t thought about the co2 dissolve issue. Thx for saving me time, energy and money. Taking a second look, its not going to work due to the ph issue you pointed out.
@anon32470837, looking at the nozzle you use, I feel it might be a bit of an overkill for the chamber you have, meaning it cant syphon from up to 2-3 meters, which imo is alot. That could be one of the reasons you get these results. I’m thinking a lower number from the parts list could be a better match.
In addition the cfm of the solenoid is curtail as well.
Take a look at
https://monstergardens.com/the-microfog-low-pressure-carbon-fiber-atomizer-1-4-inlet-output.html.html
According to the spec:
I ran couple of tests with it with different psi levels - from 30 (which I think its the 50 micron size) down to 20. Looks like it performs best at 28. But that is based on a 18" syphon line - too long imo and a very bad solenoid.
last one is with a cap without the ultrasonic tip.
In one of the videos where I dropped it to 20 psi It did not mist at all due to the syphon line going out of the water rez
Imo there is a potential if the nozzle line is 2-3 times shorter, its gravity fed and there is a proper solenoid that has good cfm flow. I would use 3/8 tubing and fittings, more precise regulator - 0-60psi.
https://www.amazon.com/dp/B018WRJYPY/?coliid=I6XM4OULKPTO9&colid=1RGZ7VN2HOE44&psc=1&ref_=lv_ov_lig_dp_it - but the 3/8 version if available. If not the 1/4 has to be taken apart and drilled with 3/16 to make the air line whole bigger to allow better air flow - same for the push fittings.
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