What cycle times on/off work best??

I have recently built a fence post aero system. I didn't use sprayers just drilled holes in the pipe between plant sites so the splatter hits the net pots. What I have been unable to find is what cycle times to use. So tell me what you think. How long on and how long off for the pump???

How many sites?

faller200 said:

I have recently built a fence post aero system. I didn't use sprayers just drilled holes in the pipe between plant sites so the splatter hits the net pots. What I have been unable to find is what cycle times to use. So tell me what you think. How long on and how long off for the pump???

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Just stumbled across this looking for good info re: hpa, sounds like what you have is SPLATTER PONICS , seriously, it takes the right MIST (i.e 20-50 microns) before you even need to think about cycle times, unless everything I've read on the subject of hpa is wrong. It takes a lot of tweaking and tuning to mist the roots with just enough moisture they can absorb, before the time the next mist cycle comes around. With a pause for reacting with the oxygen the off time helps provide. But...................IDK
maybe SPLATTER PONICS will be the next new hydroponics! BTW there is no personal criticism here it is all about the subject!

1MIN on///10 MIN OFF best for aeroponics

Most of the preset cycle timers are set at 1 ON 4 OFF. You can get adjustable to tweak things if you want, I've changed mine to 1 ON 2min OFF to get more feeding, and to 1 min ON 6 OFF to help keep res temps down, might not seem like much but i was able to drop res temps 2F avg just by cutting the pump run times back. In a low pressure system, some people let it run 24/7 on just a dribble..NFT style, as long as temps can be controlled.

If the roots are dripping wet after 10 seconds theres nothing to be gained from running it a full minute, wet is wet. If your nozzles do 20-50 microns the mist will hang for 2-3 minutes and all you`ll need is a very short misting every minute or two to maintain a constant translucent haze. The haze level needs to supply the roots with the perfect amount of water/nutes (in droplet form) for the plants needs at that particular moment and also allow the roots unfettered access to the 21% atmospheric O2 surrounding them at the same time. Most aero is run with varying degree`s of wet/dry due to limitations with nozzles,coverage, timers etc, its unavoidable, but if you can blur the wet/dry boundary to the point where both wet and dry cease to exist. you`ll have aero in its purest form.

Atomizer, have you ever used HAGO atomizing nozzles? I'm about to try 6 of them with a aquatec 6800 1/4" line> Pressure switch> 2 gal accumulator>solenoid.

Nope, havent used those but theres not a lot of variety available where i am. Adding an adjustable pressure reducer between the tank and the solenoid will give you a constant output pressure.

Atomizer said:

Nope, havent used those but theres not a lot of variety available where i am. Adding an adjustable pressure reducer between the tank and the solenoid will give you a constant output pressure.

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I won't post a link, I'm not promoting them, never tried them. But looking at the data sheet, my B100s which cost $6 each online will do 35-30um droplets at 60-80PSI. Their B37 nozzles will do the ideal 50 um at ~45 PSI.

After reading the epic fatman7574/Atomizer/Tree Farmer thread from 2010, it seems too good to be true that you could get 50 um at that low of pressure. I'm trying to do HPA, but 45 PSI doesn't sound like the HP I've seen talked about.

I have no experience, but I was a NASA engineer. I'm in Colorado now, and I want to put my skills to use. Will be starting first grow(HPA) in a few weeks.

The GPH in the datasheet is confusing though, for B100, can't tell if it is 100 or 1 GPH, not good

To get a 5-80 micron droplet range, the sauter mean (D32) will be around 21 microns. You`re looking more 300psi than 45psi

Atomizer said:

To get a 5-80 micron droplet range, the sauter mean (D32) will be around 21 microns. You`re looking more 300psi than 45psi

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Are you saying that a mean of 50 will have droplets at the high end that violate some sort of max droplet size constraint that seriously diminishes the advantage of HPA? Should I not use the B100 at 60-80 PSI
'

The sauter mean (SMD) isnt as useful as volume median diameter (VMD).
Here`s some info regarding VMD and DV values
http://pesticidestewardship.org/drift/Pages/UnderstandingDropletSize.aspx
Here`s a example of a nozzle spec with a droplet range of 5-80 microns

Atomizer said:

The sauter mean (SMD) isnt as useful as volume median diameter (VMD).
Here`s some info regarding VMD and DV values
http://pesticidestewardship.org/drift/Pages/UnderstandingDropletSize.aspx
Here`s a example of a nozzle spec with a droplet range of 5-80 microns

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Atomizer,

I asked this on a different thread that maybe you stopped checking... Can I use a 5 gallon bucket from Lowes for 1 or 2 plants and one nozzle? Planned to have nozzle at bottom pointing up.

Its not a lot of space, you can give it a go but i think you may become a victim of your own success when the bucket is full of roots and the mist has nowhere to go.
I prefer larger chambers with the mist firing horizontally into clear space between plant sites.

Atomizer said:

Nope, havent used those but theres not a lot of variety available where i am. Adding an adjustable pressure reducer between the tank and the solenoid will give you a constant output pressure.

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I decided to use a 45 gallon tote. 36" L x 21" D x 19.5" H. I did a test of just one nozzle pointed down, and the pump(aquatec 6800), no accumulator, total 1/4 flex pipe length ~2 ft.

HELP:
After a one second pulse, the water continued to come out for about 5-6 seconds in a trickle(kind of a mist but not atomized) and then dripped for about 10 seconds with big drops.

1.) Is there a simple component I can add to stop post shut off flow?

2.) Does the dripping mean these nozzles won't be good fit for HPA? I heard Atomizer uses netafim...

3.) Is a brass solenoid($10 amazon) ok to use? I'm a mechanical engineer with electrical/software tendencies, don't know anything about the chemistry. What is the standard solenoid around here? I'm looking for 1/4" and 12VDC. Just found this http://amzn.com/B00APD49BS, SS only $22(too cheap?).

Thats the line depressurising through the nozzle, same thing happens as the line pressurises. Netafims equipped with an adv start and stop misting instantly with no dripping.
Using the pump for the test versus accumulator / pressure reducer/solenoid just compounds the poor mist performance as the pressure will ramp from zero to max psi and max psi back to zero during a single mist pulse. The solenoid can release nutes instantly at a constant pressure (80-100psi), the accumulator will provide all the flow necessary. In comparison, the pump has slow response and very wide pressure variations.

Brass is ok in small quantites, a 1/4" brass solenoid isnt an issue. If you can get a stainless solenoid for a few more $ ..go for that but if its an extra $50 rts not worth it

Hope this isn't considered hijacking the thread, no other activity on this forum, though.

Nozzle dilemma:
I cannot find Netafim Pro Foggers to save my life, Netafim doesn't even have them on their Amazon. The Hago B series Atomizing nozzles from mistcooling.com don't have anti-drip feature. They even have better M series, and several different inline anti-drip adapters, but none of them have the correct threads.

Possible Solution: KBN Ceramic Nozzle $11 <link>
I like the green one for flow rate, but no drop diameter is listed, so I think I'll go with Red (0.36 mL/s @~80PSI, 35[um] mean drop size,50 degree hollow cone)


Atomizer, do you think the Red will work, perhaps it is too small(clog, wear issue?) Also, I read somewhere that you had never used hollow cone. Does anyone think hollow cone spray pattern will diminish the HPA process?

I have a few hollow cone nozzles gathering dust somewhere. The hollow cone isnt an issue as long as it can provide full coverage for the duration of the grow. It pays to think like a root when deciding where to put nozzles.

Atomizer said:

I have a few hollow cone nozzles gathering dust somewhere. The hollow cone isnt an issue as long as it can provide full coverage for the duration of the grow. It pays to think like a root when deciding where to put nozzles.

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Here is my nozzle layout plan. 4x 50-degree hollow cone horizontal, halfway up the walls. I think the hollow cone will actually be good, because no mist will be directly on any plant. Just gotta test it on Thursday when they get in. Do you think the tee and the two branches is an okay layout to keep adequate pressure(not what I call ideal)?

The drawing is to scale(except for the tubing/fittings). The angles shown should be to scale too.

Atomizer said:

I have a few hollow cone nozzles gathering dust somewhere. The hollow cone isnt an issue as long as it can provide full coverage for the duration of the grow. It pays to think like a root when deciding where to put nozzles.

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Do I need to be able to feel droplets if I put my hand where a root site should be? Or is the raised humidity in the chamber enough? I don't feel any mist in the corners.

I think I may need to go with higher flow nozzles, the spray is just not filling the entire container. I tried other configurations, from bottom, from top, longer spray. The spray pattern does not go very far on the outer nozzles, pressure must me dropping too much. I'm only in 80-100 PSI range. Do you think getting a higher PSI pump like 160 PSI aquatec 8800 will lessen that problem?