Real world Hi-Pressure Aeroponics

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deeweromekoms

Active Member
Bob Smith said:
Deewe, what temps did you notice as being "too high", and was that while vegging or flowering? If vegging (especially 24/7), I can see how temps too high in the rootzone would be problematic.

Also Deewe, are you running an accumulator setup? If so, it's doubtful that your tank can handle pressures over 100PSI..........make sure to check that - I had to search far and wide for an accumulator that could handle the pressures I wanted to run.
Click to expand...
What's too high? Lets say, ~80-85 ambient. :-(
end veg/entire flower
If you go to the original post with pic's you can see my set up as it runs, with the pump dialed in @50 psi. (max) With the accu tank the pressure drops to ~25 psi before the pump kicks in, so there's a pretty large differential.
My intention is to go as follows:
Get an on-demand pump, set it @ ~90psi, so the pressure switch will do it's thing. If no presssure swith, will build one in the line.
Then a small (2 gal?) accu tank rated at 125psi. This way the differential will be minimal (larger tank, larger diff.) Considering tanks are always rated with at least a 50% margin, with a safety pressure valve in the line it's all good. This set up needs to push ~100 nozzles.
Any thoughts?

ps - to all of you new to this, one major thing I forgot to mention is this:
100Mu FILTER!
You must build in a 100 micron filter (or whatever your nozzles require) or you will be in a world of pain in a very short time.
 
B

Bob Smith

Well-Known Member
deeweromekoms said:
What's too high? Lets say, ~80-85 ambient. :-(
end veg/entire flower
If you go to the original post with pic's you can see my set up as it runs, with the pump dialed in @50 psi. (max) With the accu tank the pressure drops to ~25 psi before the pump kicks in, so there's a pretty large differential.
My intention is to go as follows:
Get an on-demand pump, set it @ ~90psi, so the pressure switch will do it's thing. If no presssure swith, will build one in the line.
Then a small (2 gal?) accu tank rated at 125psi. This way the differential will be minimal (larger tank, larger diff.) Considering tanks are always rated with at least a 50% margin, with a safety pressure valve in the line it's all good. This set up needs to push ~100 nozzles.
Any thoughts?

ps - to all of you new to this, one major thing I forgot to mention is this:
100Mu FILTER!
You must build in a 100 micron filter (or whatever your nozzles require) or you will be in a world of pain in a very short time.
Click to expand...
I got a 1 micron filter (two of them, actually) for $5 a piece from McMaster Carr (I'll see if I can find the link).

FYI, those pressure switches on pumps are notoriously unreliable and drift a lot - that's a large reason why I got an external switch, even though my pump technically has its own pressure switch.

A couple of thoughts - operating a tank above its recommended working pressure is a bad, bad idea from what everyone has told me - even though it might not blow up, it won't work as well as a tank designed for higher pressures.

I run 30 nozzles off of a 4.4 gallon accumulator, and my pump comes on about once an hour (for thirty seconds) since I've switched to a 5 second on / 2 minute off feed time (just to make sure these clones throw out some good roots) - I highly, highly, highly doubt that a 2 gallon tank could service 100 nozzles in a very efficient manner.........the pump would be coming on almost at every cycle, or every other cycle-ish..............no matter what the math tells you, reduce that by a factor of 2 to account for run on, drip, etc. I'm actually looking at upgrading my accumulator sooner rather than later to a 20 gallon+ setup, if not a lot larger than that.

How many solenoids do you plan to have feeding these 100 nozzles? Depending on your exact layout, I'd say you're gonna need at least 15-20 solenoids............that gets expensive and complicated. I have four solenoids feeding 30 nozzles and feel like I could have more (but I can get by with what I have)...........
 
Mike Young

Mike Young

Well-Known Member
Bob. Where would you get a 20 gallon accumulator? These things seem pretty simple. Anybody ever look into building one from scratch? I was thinking I could build one out of the 10" pvc I have. It's really thick and appears it could handle the pressure. Just need a couple of caps and a bladder, correct?
 
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Atomizer

Well-Known Member
deeweromekoms said:
If you go to the original post with pic's you can see my set up as it runs, with the pump dialed in @50 psi. (max) With the accu tank the pressure drops to ~25 psi before the pump kicks in, so there's a pretty large differential.
Click to expand...
Quick suggestion, use a pressure regulator/reducer between the tank and the solenoid. For example run the tank from 200psi - 100psi and regulate the output to a 100psi. The tank has a large differential but the output remains constant.
 
B

Bob Smith

Well-Known Member
Mike Young said:
Bob. Where would you get a 20 gallon accumulator? These things seem pretty simple. Anybody ever look into building one from scratch? I was thinking I could build one out of the 10" pvc I have. It's really thick and appears it could handle the pressure. Just need a couple of caps and a bladder, correct?
Click to expand...
PVC CAN NOT HANDLE THAT PRESSURE!!!

Yowsers, please don't do that...........sorry for the caps, but you'd be building a bomb.

Here's a post I wrote at another website ten minutes ago - the first link is the manufacturer I got my tank from - they're made out of steel with a special bladder to keep the air/water separated (the tank much be precharged with an air pump to 2PSI less than the minimum operating water pressure; i.e., I precharged mine to 98PSI because I'm operating from 100-125PSI).

"Pick your poison on which of these tanks you want - this is the only manufacturer (to my knowledge, after lotsa searching) that makes tanks rated up to 150PSI (in the US, TF said he had to order from overseas for his high pressure tanks):

http://www.pexsupply.com/THERM-X-TROL-Tanks-354000

I'm looking at upgrading to the 34 gallon, personally.

Then you're gonna want two of these pumps:

http://www.steam-brite.com/store/shu...ls-p-4296.html

A Grainger pressure switch like the one I got (set for 100-125PSI), and then a backup set for (throwing out a number here) 90-98PSI, or something like that.

http://www.grainger.com/Grainger/pre.../N-8gnZ1z11l12

Depending on how many plants/misters you're running, you're gonna need a few of these:

http://cgi.ebay.com/1-4-Electric-Sol...item43a492a46e

Then you need your misters, your adapters (to connect the misters to the tubing - I didn't look around, but if you could find misters with built in quick connect fittings, you'd be sitting pretty - the adapters are like $5 a piece, which adds up with lots of misters), your fittings, your tubing, pressure relief valve, pressure gauge........and I think that's about it - oh, you're DEFINITELY gonna wanna get a UPS to account for power outages - a small one (like 250 watts) would cover you for a day+ (actually a lot more if you got a large expansion tank).

Knowing what I know now, I could (IMO) pretty easily setup a room your size for half your budget.

Pressure tank - $250 (go big, it's definitely worthwhile, IMO)
Two pumps - $250
Two pressure switches - $125
Misters (assuming 40) - $60
Tubing, fittings (this is where you get ASS FUCKED) - $500
UPS, miscellaneous - $250
Solenoids (assume 10) - $150

Even going high on the tubing/fittings number, you should be able to pretty easily do your setup for $1500, $2K at max."
 
Mike Young

Mike Young

Well-Known Member
Ok. I was just throwing the idea out there. I would only run at 50psi, but I was well aware of the potential. I used a.b.s. to build my potato gun...hehe. I guess I figured that if the 1/2" is rated at 600 psi, that it could handle it. And it likely could, but not worth the risk. I gotcha. Now that I see a 20 gallon is only $230, I wouldn't fathom trying to build my own. You are the man at sourcing parts. I looked at accumulators, and didn't come close to matching those prices. Nice work!
 
B

Bob Smith

Well-Known Member
Really the tanks are my only contribution (and they can be had on eBay for cheaper - my 4.4 gallon was $50, delivered) - the rest are links people have provided to me or that I found from the "Forget the Fogger, I'm going HP aero" thread over at Gardenscure.

Really a great and informative read if you haven't taken a look at it - it's 66 pages and I've read it front to back three times in the past month.
 
Mike Young

Mike Young

Well-Known Member
I will have to pick up & read more later. He certainly does a great job of documenting. I'm kicking myself for not finding threads like his before building mine. Oh well. Coming into this with zero experience in growing or growning systems, i'm happy with the way it came out.

How's the build? I havent seen an updated vid on youtube... I assume there are more kinks to work out?

Atomizer. By chance, you have any info on the system you run? You haven't started a single thread, nor from what I gather mentioned anything about your personal setup. Just curious. I can imagine that it's something to behold. Your advice has always been dead on. Sometimes a tad harsh... but precise none the less.
 
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Bob Smith

Well-Known Member
Build is pretty much done (after another mod today), but there are plants in it now (have been for almost a week)..........if you'll notice on my videos, you don't ever see a plant, and there's a good reason for that :) ..........so unfortunately, a video of how it works will have to wait until the system is empty again, which won't be for a few months.

I have a build out thread at THC Farmer where I document most of my shit at............lots of pics I need to upload, will get to it soon enough.

And I wouldn't hold your breath on any UK folks to post pics of their grows - their Internet privacy is almost nil over there, which is why you see so few pics of their grows (IMO).

BTW Mike, where'd you source your 6" PVC from? I know the Home Depots and Lowes by me only go up to 4" - where's a good spot to look for larger diameter pipe at?
 
Mike Young

Mike Young

Well-Known Member
Mine is 10". I happened upon it unconventionally. A friend of mine in the construction ind. happened to notice some fall off the truck, if ya know what I mean. JM Eagle is the manufacture. I was told that it goes for about $20 per/ft. This is sewer pipe, and is really thick. You could probably get thinner stuff to save on $. They have it upto 48" diameter. I'd like to have some 15" to replace my 10" pots.
 
PetFlora

PetFlora

Well-Known Member
BobS. Thanks for the link. It was deja vuo for me, as it so paralleled where I started. He even copied my Zen Moment comment from 2 years ago, which I copied from Pod Racer, but added the "Zen Moment" when I posted it to my journal.

The main issues are his pots are neither deep nor wide enough (he did say he wishes he had bigger pots), so he is compensating with a screen, but the screen turns True Aero (where roots do not touch the sides/bottom) to Faux Aero. Also his feed times are still too long.

FYI someone somewhere posted not to close the lid on your rez, which I was doing (I THANK YOU). And even though I kept frozen jugs in there, the humidity in my root pod was hovering in the low 80s. Since opening it, the RH in my root pod has dropped to low 40s without using my DIY pod chiller, so I need to slightly close the lid to get it up a bit, but the pod never smelled fresher. MEGA PROPS
 
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Bob Smith

Well-Known Member
Mike, thanks - plugged in my zip code and came up with nada within 50 miles.........methinks I'm gonna have to build something outta PVC board, or maybe I'll just tear down my octagon and grow trees.........lotsa time to decide.

Pet - what link are you talking about? The "Forget the fogger" one? And it's pretty much impossible, IMO, to have roots not touch the bottom of a container without a screen.......I've grown 2' tall plants with 8' long roots in lp aero/NFT.........can't imagine what container size I'd need for a 5-6' plant - four stories? That's not very practical........so long as the roots aren't being bathed in solution runoff (by being suspended in air via a screen), I think it qualifies as HP aero (just my opinion).
 
Mike Young

Mike Young

Well-Known Member
That sucks. I did the same and found a place 2 miles from my house. I agree on the root growth. My clones only took 30 days for the roots to strech out 2' to the bottom of my pot. My plants were only 10" tall at the time. 16" wide though. :) Now that I have the scrog net up, I'll not be able to see the roots til completion. Last I checked there was a cantelope sized ball that had formed at the bottom. That was about 2 weeks ago. I think in two months I'll have a 2' x 10" root cylinder. And a few oz's of bud to match.
 
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Bob Smith

Well-Known Member
Not a big deal, really - I didn't wanna have to make another vertical PVC "experiment" anyways (already gonna have a couple grand of spare PVC laying around soon enough)..........will run this one for a couple of runs ( or until I get it dialed in, tire of it, or decide that fewer plants would behoove me on a legal front, whichever comes first). Then I'll either do four trees rotating on their own turntables around my light source (drain to waste hempy buckets, as HP aero would be impossible with that setup), or four trees in 50 gallon containers utilizing HP aero scrogged around that central light source.

Or I might go back to my roots and do horizontal lighting SOGs with custom built PVC chambers (HP aero, of course).

Can't remember what your drain on your buckets is like, but before you're too overgrown in there it might be a good idea to put some sort of screen over it so it doesn't clog.

And Pet, why would you want to limit humidity in your rootzone? And if you do, wouldn't misting less accomplish that goal as opposed to opening the lid and allowing light inside? Lucky for my my root zones are nowhere near air tight anyways (but they are light tight).
 
D

Deximus

Active Member
Mike Young said:
Ok. I was just throwing the idea out there. I would only run at 50psi, but I was well aware of the potential. I used a.b.s. to build my potato gun...hehe. I guess I figured that if the 1/2" is rated at 600 psi, that it could handle it. And it likely could, but not worth the risk. I gotcha. Now that I see a 20 gallon is only $230, I wouldn't fathom trying to build my own. You are the man at sourcing parts. I looked at accumulators, and didn't come close to matching those prices. Nice work!
Click to expand...
You can build your own accumulator pretty easily if you are handy and have the space. 10" Schedule 40 only has a working pressure of 84 psi for inspection purposes, but carries a minimum bursting pressure of 450 psi. You could use it, but it's not a good idea ;)

3" and less schedule 40 has an operating pressure of 150 psi or higher, with burst pressure starting at 840 psi. A bladder system is convenient, but unnecessary. Propane tanks are rated for 250 psi, and then are built with something like a 4x safety margin. You can only put air in it of course. I was going to build something like this if I wanted more draw down volume:
acc.GIF

There are conversion kits for the left-hand thread on propane tanks to allow them to be used for compressed air. I would probably just weld an iron fitting on myself. If I used a 5 gallon tank and operated between 100 and 150 psi, I would want the storage piping to be 2.4 gallons. A pair of 4' long, 3" pipes would give room to spare at ~3 gallons.

To start from depressurized, I would fill the plumbing with water to the bottom of the large pipes, then pressurize the air tank with an air compressor to 98 psi. One could conceivably do all the work with the water pump, but it would take some fancy valve effort to work the air pressure up using water alone.

The air will slowly get taken into the water, which would make the water level rise over time. I have the feeling it would take quite a while before running the risk of water going over the top and into the tank though. Sloshing paint around the inside of the propane tank would be a good precaution against rust.
 
PetFlora

PetFlora

Well-Known Member
Bob Smith said:
Not a big deal, really - I didn't wanna have to make another vertical PVC "experiment" anyways (already gonna have a couple grand of spare PVC laying around soon enough)..........will run this one for a couple of runs ( or until I get it dialed in, tire of it, or decide that fewer plants would behoove me on a legal front, whichever comes first). Then I'll either do four trees rotating on their own turntables around my light source (drain to waste hempy buckets, as HP aero would be impossible with that setup), or four trees in 50 gallon containers utilizing HP aero scrogged around that central light source.


Or I might go back to my roots and do horizontal lighting SOGs with custom built PVC chambers (HP aero, of course).

Can't remember what your drain on your buckets is like, but before you're too overgrown in there it might be a good idea to put some sort of screen over it so it doesn't clog.

And Pet, why would you want to limit humidity in your rootzone? And if you do, wouldn't misting less accomplish that goal as opposed to opening the lid and allowing light inside? Lucky for my my root zones are nowhere near air tight anyways (but they are light tight).
Click to expand...
From a mj grow guide
"Temperature

The ideal temperature to grow marijuana is around 75 degrees F or 24 degrees C. Plants though can survive from around 40 degrees F (5 degress C) to 100 degrees F (38 degrees C). Humidity in the grow room should be kept between 60- 80%. Above 85 % and the risk of mold is greatly increased."
I can attest to the funky smell when mine was hovering around 80 last week.
 
B

Bob Smith

Well-Known Member
PetFlora said:
From a mj grow guide
"Temperature

The ideal temperature to grow marijuana is around 75 degrees F or 24 degrees C. Plants though can survive from around 40 degrees F (5 degress C) to 100 degrees F (38 degrees C). Humidity in the grow room should be kept between 60- 80%. Above 85 % and the risk of mold is greatly increased."
I can attest to the funky smell when mine was hovering around 80 last week.
Click to expand...
Lol..........that's "grow room", partner.

I keep my RH in the 65-70% range during lights on (until late flowering) and drop it to 55% at lights out.

You were talking about your reservoir...........and that temp is incorrect for people like me enriching with CO2 - my plants grow 2X as fast at 83F as they do at 75F.
 
PetFlora

PetFlora

Well-Known Member
Bob Smith said:
Mike, thanks - plugged in my zip code and came up with nada within 50 miles.........methinks I'm gonna have to build something outta PVC board, or maybe I'll just tear down my octagon and grow trees.........lotsa time to decide.

Pet - what link are you talking about? The "Forget the fogger" one? And it's pretty much impossible, IMO, to have roots not touch the bottom of a container without a screen.......I've grown 2' tall plants with 8' long roots in lp aero/NFT.........can't imagine what container size I'd need for a 5-6' plant - four stories? That's not very practical........so long as the roots aren't being bathed in solution runoff (by being suspended in air via a screen), I think it qualifies as HP aero (just my opinion).
Click to expand...
Yours is a good compromise. Having had that very problem during my last grow, which was bag seed, and turned out all were sats, the roots grew so long that I had to buy 2 extra totes, cutting the bottom out of one, the top out of the other and stacking them to keep my roots from hitting bottom. This raised the top of canopy to some 8ft off the floor. I ran out of head room, and they were too old to bend. This is one of the reasons I went with AFs this time, the other being I hoping to be able to quai- SOG.

right now. the roots of one plant are getting close to hitting the bottom, but its been ~ 70 days, the damned plants should be harvested by now (unstable genetics- neither plant is developing as described- privately purchased), but have yet to begin budding. Four days ago, I cut the light back from 20/4 to 12/12 . No pistil clusters yet, but that have that ready look about them.
 
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