HPA Without An Accumulator

[PetFlora]

I know many of you want definitive steps to follow, but there are simply too many variables. The good news is as long as you are in the ball park, your plants will do amazing things. and the closer you get, the greater the rewards. Besides, how much reality programming can you watch?

My starter system uses a cycle timer whose lowest setting is 30 seconds (needs to be replaced to a more expensive timer with much lower on cycles). I am finding that the minimum of 30 seconds in my starter system is way too long for young developing plants. Two days ago I was forced to move 4 plants that are 5 weeks old out of my starter system and into my main system because their roots had already reached the bottom of the 15" deep pod.

Worse, the roots were beginning to take on the appearance of DWC roots- overcooked slimy spaghetti. Proper roots are loaded with lateral roots that make them look like fish bones. You won't get them if the pod environment is constantly damp and wet. Roots need some dry time between feedings to process the nutes, as well as to develop the lateral roots.

In the main system I can adjust feed cycle down to 2 seconds. I decided to start with 5 seconds as these were getting 30, and am monitoring how the roots (and plants) respond. So far, so good.

Once the plant is well into flower mode, increasing the feed time 'might' be a good thing. I will soon see. I am hoping it is not the problem that the developing roots had, which forced me to move the 4 plants to my main system, which meant having to move my one flowering female, who is 2-3 weeks from harvest, into my starter system with 30 second minimum feed cycles.

It's been 2 days and she seems no worse for wear, but her roots were well established, so she may be better able to handle the longer feed cycle this late in her life, which is 2-3 weeks more. Time will tell.

hth
____

 

[rosecitypapa]

PetFlora, have you noticed anything with plant health and growth with that HHG in your garden?

 

[PetFlora]

I have no idea what HHG is, but plants are doing very well. Pics Saturday. OH, I get it now HHG- holy ... am I right? I keep them in the pods, on my computer, corners of the house, in my car, around my neck, and have gifted tons of towers in a 15 mile radius of where I live.

People do comment that they really like the head.

 

[rosecitypapa]

I have no idea what HHG is, but plants are doing very well. Pics Saturday. OH, I get it now HHG- holy ... am I right? I keep them in the pods, on my computer, corners of the house, in my car, around my neck, and have gifted tons of towers in a 15 mile radius of where I live.

People do comment that they really like the head.

Yeah, orgonite is interesting. The before/after photos of vegetable gardens under the influence of them got me really fascinated. I've been casting a bunch and also experimenting with plasterite now (using plaster instead of resin and no metal - just beach sand).
This isn't really a good test since I've changed so many variables, but the buds I'm growing now are the biggest colas I've grown.

 

[PetFlora]

I am afraid that the spirited debate here as to whether my set up is High Pressure has turned many off who would benefit from my method, which was pointed out has more in common with F &D, but my spin moves it into the 21st Century, rivaling THPA results.

Also my tinkering with feed times has confused many, but you can grow outstanding plants using 5 second feed with 15 minute pauses-24/7. Since DM was formulated for hydro and mj, I highly recommend them. Although I am using the full Gold line, I will likely simplify and switch to ONE + Silica + Zone. Once you have a few grows under your belt you can then experiment with feed time and pH variables.

Let me simplify why and how...

Where FD uses a medium like gravel or Rock Wool, mine uses no medium beyond the starter cube for seedlings- only a foam inserts for clones. With a couple of simple precautions, gone is the probability for root rot, pythium, etc.

Instead of plant roots growing in a medium, they hang inside a pod where, instead of being flooded several times a day, they are misted using a high pressure pump and high pressure, low flow mist heads which combine to turn the nutrients into an atomized fog. This fog is much easier for the microbes living on the roots to consume. This allows for several beneficial differences from conventional F&D. Why is this better?

1. Taking a page from what nutritionists know about our need for nutrients, we function better and it is healthier eating 5-10 small meals a day instead of gorging 2-3 times a day.
2. Roots are misted ~ every 15-30 minutes for ~ 5 second intervals. Times are not cast in stone as other variables must be considered, like age of plant, nute strength, temps, root and pod size.
3. Much lower nute strength fed more often accelerates growth. High ppm nutes are unnecessary and potentially harmful.
4. Recirculating nutes is a disaster waiting to happen. Some portion of nutes from each feeding has been used by the plant. This means the leftovers no longer have the nute balance that exists in the 'virgin' rez. pH and toxic problems are sure to follow. This can be somewhat compensated by using buffers, but why put a Band-Aid on a shotgun wound?

Due to lower ppms combined with minimal feed times, nutrient cost is negligible.

Updated pics tomorrow

hth

 

[Atomizer]

You made a complete u-turn in timings but its not confusing. You`ve switched to a timing range more suited to your delivery method, some may notice how it bears an uncanny resemblence to the timing used for lp aero

 

[PetFlora]

Atomizer: I believe it was you who said my method has more in common with F & D. I had no problem considering it as my very first grow 30+ years ago was F & D, using a low pressure low flow pump, a simple 15 minute timer, which was only used in 4 hour blasts, and 1000 watt metal halide. It mos def produced trees.

Feed Times

The majority of low pressure system threads and journals seem to be using 15 minute feed times, far from 15 seconds or even 30 seconds
I am still playing with times, but here's a recent observation. My backup system also has an Aquatec 8800 and same mist heads (sourced from Reptile Basics. BTW, their heads articulate, which I find very helpful in aiming the spray) but instead of a Sentinel MDT-1 timer, it has a lowly IGE, whose lowest setting is 30 seconds. So I was forced to deviate.

I moved my then 4 week old plants (started in a bubbler) into this IGE timed system. First week the roots were growing laterally as well as deep, and this threw me. However, by the second week the roots stopped developing laterally, began looking more like DWC slimy long spaghetti noodles.

This came about because I was trying to finish my AF hybrid in the MDT-1 system, but had to swap due to the root issue. Since moving Lonely Lady into the IGE system 4 days ago,trics have quadrupled, plus I notice some new root development. This makes me think in my 21st Century F & D system that there might be some benefits in early veg- mid bloom- and late bloom to change feed times. I will experiment on this new grow.

The learning curve just keeps going. Posting new pics tomorrow

 

[Atomizer]

The majority of low pressure system threads and journals seem to be using 15 minute feed times, far from 15 seconds or even 30 seconds

You missed the point, if the roots are soaked in 15/30 seconds they won`t be any wetter after 15 minutes. Typical lp aero timing is 1min on /4mins off, most pond pumps used in lp aero setups could handle a 15 second on time.
The thread title isnt accurate now with all the changes, (hpa without an accumulator) as your u-turn in cycle timing confirms the standalone pump approach doesnt emulate hp aero.
You seem to have lost sight of the constant feeding benefit of hp that you mentioned regularly in your earlier posts. Your well defined wet/dry cycle is very different to goals of HP (a short cycle timing delivering a very low volume of mist) to maintain a constant balance in the chamber enabling the roots to feed and breathe at the same time.

 

[PetFlora]

If the mods can/would change the title I would like to change it to 21st Century Flood & Drain: I have done so on another site.

I have not lost sight of deep cycle feed times, however, I strongly disagree with your statement that 15 second feeds from high pressure low flow mist heads soaks the roots as much as a low pressure pump watering for 15 minutes.

Due to Lonely Girl not behaving like the AF x that she is, instead she has taken her sweet time to finish just as she did to grow. She was in the main system getting < 5 second feedings. I had no choice with the 4 new plants but to run 30 second feed times as that system has a IGE timer (which I said needs to be replaced) whose lowest on time is 30 seconds. Sadly, the 30 second feed time hugely accelerated their root development, forcing me to move them into the main rig which has a Sentinel timer, that can be set for one second, but is not accurate there.

So the 4 plants in the main rig have been getting 5 SECOND feedings, but I just reduced to 4 seconds (hardly lpa feed times). Although I wanted to finish Lonely Girl with < 5 second feed times, I was forced to move her to the IGE set up. Funny, but since doing so her tric development has quadrupled and she is sprouting new roots. MAYBE, just maybe, increasing feed time during mid-late bloom has benefits. Clearly it is helping to fatten her up.

Today's pics...

 

[Atomizer]

If the roots are wetted to the point water runs off in 15 seconds..they`re not going to get any wetter. The water will simply be running off for a longer period of time. The drying time begins when the misting ends so you will get more cycles from the shorter misting duration.

Deep cycle feed times (as you put it) have nothing to do with constant feeding, the cycle timing simply facilitates the correct mist environment surrounding the roots so they remain at the ideal dampness (for want of a better word) 24/7, they take what they need from the mist when they need it.. nothing is forced on them. They don`t get wet and they dont need time to dry out...constant feeding.
Your interpretation of what constitutes hp aero is a country mile from mine and others. The two methods are not interchangeable, simply adopting the hp parameters that your setup may be capable of doing isn`t enough as you`ve discovered.
At the end of the day, if your take on it provides a result you`re happy with, thats all that counts.

 

[PetFlora]

Atomizer: I think you finally got it into my thick skull. In my last grow I was using < 2 second feed but more like 5 minute pauses, where I now understand the pauses should have been in seconds as well.

Today, I began feeding the 4 plants @ ~ one second (the Sentinel MDT-1 is not accurate at one second, not sure if it is less or more), but it's the lowest on time available.

I am now dialing in the pause, currently at 40 seconds (roots are damp, no more droplets hanging on them.

I was misting with 3 heads. I removed the dual head mister, now only a single 0.92gph head.

In the end, VPA will not function 100% as a THPA system does, but the results are still pretty amazing., and now that I have a clear understanding of the pause cycle, they should be moreso.

Thanks again for the continued info/help!

 

[Atomizer]

I highly recommend testing the nozzle so you know exactly how much water its putting out. Its essential to know the real flowrate as it determines the maximum misting duration.
The misting pulse creates the balance, the pause maintains it. Given perfect coverage and an ideal droplet size range, a single 0.92gph nozzle would be more than sufficient for a 50gal+ chamber.
To test a nozzle, place a plastic bag over the nozzle and collect all the liquid it delivers during a 2 second misting pulse from beginning to end. Place an identical plastic bag (bone dry) on a set of digital scales (grams) ideally accurate to 0.1g and hit the "Tare" button. Now weigh the wet bag and convert the weight to a liquid measurement (1g = 1ml).
Let us know the result.

 

[PetFlora]

First, I have been using ~1 second/40 second pause since 9:30 am yesterday; around 6:30 pm I lowered the pause to 30 seconds, giving them 7 hours of light at that cycle. My pump cycles 24/7. Around 6:30 this morning the plants look great and growing, certainly no worse for wear, having reduced feed cycle from 5 second/12 minute pause. I will reposition the mist head higher up, so more mist is falling onto the hanging portion of the roots, which grew to long too fast when I was forced to start them using a timer with minimum of 30 sec on time. The good news is the roots, which looked like typical DWC slimy spaghetti is filling out with lateral roots.

FYI, the lava rock seems to be working, but I need to get more. Fighting a dead car battery for 3 days has slowed me down. Where do I buy silk screen, just in case the rock doesn't work out?

One head per 50G? WOW.

My pods are rectangular, which has the potential for dead zones (which is why I was using more heads), but I can get 3-4 mature plants in one 15G pod, as long as I am not growing anything taller than 3ft. Three reasons for not going bigger is 1) for the massive roots 2) I would have to fabricate a stronger lid to handle the weight of bigger plants 3) total height. A 3ft plant in my system takes up roughly 7ft, not including the light.

I ran the test you suggested, but my digital scale does not read out decimals. The readout for the bag keeps fluctuating between 6 & 7 gms, a second burst = 9gms. Using 1.25gm/second, I get 450 gms per hour pretty close to .92gph. Frankly, I expected a heavier result, since without an accumulator, the pump pressure is starting from ~ zero psi, BUT, the rez is higher than the pump (always has 3-4 gallons of nutes), so the pump (and probably the tubing all the way to the mist head) is fully primed.

 

[Atomizer]

0.92 gph should deliver a little less than 1ml (1g) per second, if you`re seeing 9g from the 1 second timer setting that equates to an effective flowrate of 8.5gph. Obviously, the actual misting pulse will be a lot longer than the 1 second timer setting due to the pressure in the tubing falling off after the pump stops.
To deliver 1.25ml in one second you would need the timer set to 0.138 seconds, thats a tall order even for an accumulator setup with the solenoid right at the nozzle
If your timer can`t go any lower than 1 second, then 9ml will be the smallest quantity of liquid you can deliver to the chamber in a single misting (for calculation purposes). Putting the 9ml into a hp aero context, you would need a minimum 265gal chamber to prevent oversaturation during each misting pulse and you`d really struggle to get full coverage in a chamber that size from a single nozzle. The smallest volume of liquid i`ve managed from a single nozzle is 0.2ml, the overall misting pulse was 0.3seconds with the timer set for 0.25seconds.

 

[PetFlora]

Paraphrasing Tina Turner "What's 9gm got to do with it?"

I said I am recovering 1.25gm/ second, not 9.

And as you said a .138 second time is hard to achieve, even with an accumulator. As I see it, I am closer than I have ever been, and certainly as close as I can get without an accumulator.

Thanks again. Will keep you posted with weekly pics.

 

[Mike Young]

All of this silk screen in the root chamber got me thinkin. Would it be beneficial to place a series of nets in the root zone? I'm thinkin 3 nets, 1/2" - 3/4" spacing (something resembling a tennis racket.) Like a scrog for the roots. In my head this seems like a really good idea. Thoughts?

 

[Atomizer]

I ran the test you suggested, but my digital scale does not read out decimals. The readout for the bag keeps fluctuating between 6 & 7 gms, a second burst = 9gms. .

I was using your numbers for calculations. I`m not sure how you get to the 1.25ml/second figure. How long was the misting pulse 1 second or 9 seconds overall from start to finish?

Using 1.25gm/second, I get 450 gms per hour pretty close to .92gph

450gms per hour is 0.125g per second or 0.12gph.

0.967g or ml per second is 0.92gph
1.25g or ml per second is 1.19gph.

 

[PetFlora]

All of this silk screen in the root chamber got me thinkin. Would it be beneficial to place a series of nets in the root zone? I'm thinkin 3 nets, 1/2" - 3/4" spacing (something resembling a tennis racket.) Like a scrog for the roots. In my head this seems like a really good idea. Thoughts?

Did you see my picture inside the pod? So far, the lava rock is working, but I need to get more to cover the bottom

 

[PetFlora]

I was using your numbers for calculations. I`m not sure how you get to the 1.25ml/second figure. How long was the misting pulse 1 second or 9 seconds overall from start to finish?

450gms per hour is 0.125g per second or 0.12gph.

0.967g or ml per second is 0.92gph
1.25g or ml per second is 1.19gph.

I see where the way I said 'a' second was confusing. I should have said 'one' second. 1.25 is roughly the number due to no decimal readout.

Observation, a ~ 30 seconds pause uses up a lot of nutes in a day. For large growers, a < 1 second feed would probably save them enough money to pay for the accumulator

 

[Atomizer]

The numbers are correct then, its only 1.25ml if you can get the pulse to last for exactly 1 second.
To get 9g of liquid in the bag, the physical misting pulse would have been around 7.2seconds even though the cycle timer was set for 1 second.
To calculate the timing range you need, you have to take the smallest amount of nutes you can deliver to the chamber using the 1 second timer setting..which in your case is 9g or 9ml, aka the real quantity of liquid the roots are seeing from the misting pulse, not a theoretical number on a spec sheet..
The effective nozzle flowrate for the calculations becomes 8.45gph, what you collect in the bag test includes everything..pump delay, pressure drop, mist run-on etc. Its the perfect yardstick to base mist timing calculations on, the number is unique to your setup because its what your roots are getting from your nozzle, pump and plumbing layout