Adventures in Hydro #2 - LP Aero/NFT mash-up - or - switching to HPA?

I had a sudden brain storm about a way to ‘calibrate’ the nozzles to see how much mist was hitting the roots and where it was strongest from top to bottom, which nozzles were getting the most or least mist to the roots, etc. I took some empty toilet paper rolls and stuck them in the hole where the net pot goes and waited for a few cycles.

That worked very well for the first nozzle I messed with. A minor change in angle and the cardboard tube was getting nice and wet all along its length.

However, the other two didnt seem to want to play nicely. No matter how I pointed them, I couldnt get a decent mist build-up on the cardboard tubes.

Hmmmmmm. So I took some flat cardboard cut from a box and held it in front of each nozzle in turn to check the pattern. I wanted to see if the ‘cone’ was hollow or solid. The specs were not clear on that.

Boy was I surprised to find that the ‘cone’ isnt a cone at all!! All of the nozzles actually have at least three heavy lobes to the spray with a fairly even but much finer spray pattern in between. No wonder I have been having trouble getting an even distribution of mist!!

This is the pattern from one nozzle on a long cardboard tube.

For now, I have them all adjusted so that they hit the net pot fairly evenly with a light mist. The area below the net pot is not anywhere close to even. This will be an improvement over what I had, but still not ideal.

I suspect part of the problem is that these nozzles are designed to work from 70 PSI up to 1000 PSI, and I am using them at close to the very bottom of their pressure range. Im not sure what to do about this though.

The little seedling I transferred to the root chamber of death is doing pretty good! It was kind of droopy at first, but its been two days and its looking ok.

The really good news is that, after two days of getting used to the change in environment, its started to put out new roots - and they are showing some fuzzy hairs!!

I am starting to think I may be almost getting a handle on this…maybe…

When I first transferred it to the chamber.

Today.

Some fuzzy hairs closeup.

Its interesting that I am back to my original settings - .7 sec ON and 55 sec OFF.

We have been having a very interesting discussion about PH in this thread.

and it has me second guessing my decision to lower the rez PH to 4.6.

Now Im wondering if the dramatic PH rise in the mist is really “real” or not. It also occurred to me that even if the PH rise is real, the changes may not be happening instantly or as rapidly as I thought. Ive been having some odd issues with the plants, and I keep coming back to it could be PH related. Im now thinking that the mist could well be coming out of the nozzles at the same PH it was in the tank, and its still at that PH (or very close) when it hits the roots. Then, after some time passes, and it collects in the bottom of the root chamber, it starts raising up.

So I may be hitting my roots with nutes that are way too low in PH.

The main reason Im looking at this so close is that my plants keep having odd growth up top even when the roots look good.

Here are some pics of the latest experimental torture subject. When I transplanted it from the small perlite hempy bucket, it looked pretty good. A little pale in color, but the leave all looked very healthy and there was only a little drooping from lack of watering.

This is it right before the transplant.

This is a few hours after the transplant.

Now, the new leaves are significantly darker, but they are drooping badly and the old leaves are drooping plus turning yellow and discoloring.

This is today - about 5 days since the transplant.

So, Im going to increase the PH in the rez to 5.4 or so and see what happens…

I also discovered why the nozzles have such odd spray patterns, and why those odd patterns seem to change between my checks - there is crap in the nozzles!

I have been checking into that, and I think Im going to have to get better about keeping light out of my rez. I discovered some algae growing in it. Apparently, algae can get past a 150 mesh filter. So, I ordered a 200 mesh filter to go right before the solenoids. I also added some pool shock to the rez at 3ppm to kill whats there now.

Once the filter gets here, I will flush the system, install the filter and clean the nozzles again and see how that goes. In the mean time, I need to move my main work light as it sits right over where the rez is. Im also going to work on light proofing the rez more - especially the lid and pipes.

Thanks to @Esrgood4u and @HappyHemper for helping bring this “light” issue to my attention.

I knew I needed to keep light out of the rez, but I didnt take is seriously enough.

3 Likes

The roots don’t like light at all. My red buckets were only slightly opaque so I thought I’d be fine. A week later slight algae. I shone a torch onto the side of one of the buckets and I was able to see light but not much at all. I cleaned the algae out the buckets and wrapped half a roll of black duct tape around each bucket and repeated the test until I was 100% sure I had no light penetrate at all. I’ve been fine ever since :+1:. I still pool shock them weekly though “just incase”

2 Likes

Word of the week: “Algae” lol. I hope you kill’em dead. I’m going to try and get a filter for my setup too.

I am starting to wonder if my black-inside hoses are insufficiently black inside too.

1 Like

I think my worst sin has been leaving the lid off the rez for long periods with the over head light on and the work light on right over the rez. Im adding foil and extra layers of light blocking material in various places, covering the yellow lid to block more light, and moving the work light. Plus - dont leave the lid off!!

I ordered a 200 mesh filter to install right before the solenoids. I already have 120 mesh inside the rez on the intakes and the curculating pump, plus a 150 mesh just outside the rez. The algae is getting through all those.

I also had to get one that is a bit more expensive than I wanted because it needs to withstand some moderate pressure. That line stays between 100-110 PSI all the time and the cheaper filters cant handle over 80 PSI.

I ordered the 3/4" x 200 mesh version of this one.

If you are in DWC, you will need to check the flow rate of the filters more than pressure. I have very low flow rates at hi pressures. You will have just the opposite - hi flow rates at low pressures. You are going to need a filter with more surface area so it doesnt slow down your flow rate to much.

There guys have some different ones that may work for you.

Their prices are similar to Amazon for the same things and they ship fairly quickly.

1 Like

Or you could just dump some water, nutrients and an air pump connected to an air stone into a blacked out bucket like I do. Top up once every 2 - 3 days :+1: works really well for me and the most simple form of hydro known.

2 Likes

LOL! I cant really argue with you on that considering all the different things Im juggling at the moment - clogged nozzles, algae, weird PH issues, strange plant problems, dead solenoids, etc etc.

BUT…

Im actually already doing the absolute simplest form of hydro with my seedlings and my moms - hempy buckets :wink:

Nothing is simpler than a bucket filled with perlite, or vermiculite, or hydroton, or coco, or just plain gravel. Poke a few holes near the bottom, add nute water every few days and thats it.

No air stones, no pumps, no nothin but lots of LITFA :smiley:

On days like the last several I have had, I find it really irritating that a system so simple and sooooo boooorrrriiiinnngggggg, works so dam well :smiley:

3 Likes

Ok, the last couple of days I have learned several new things that should make this better going forward.

  1. My light discipline for the rez sucks and needs to improve.

  2. Algae can easily fit through a 150 mesh filter and partially clog my nozzles.

  3. Partially clogged nozzles have weird spray patterns that change from time to time - making it very difficult to get a consistent spray pattern and coverage. The clogs also force you to use higher flow rates to compensate.

  4. Just because the runoff water has a hi PH does NOT mean the plants/roots are seeing that same high PH.

1, 2, and 3 are easy mechanical fixes with a dash of added new habits - as in keeping the lid on the rez.

4 is more troubling.

The PH in the rez, and in the accumulator tank, and right before the nozzles is now at 5.4/5.5.

The run off water is still up to 6.4/6.5 - and the plants are doing much better after just a few hours.

This morning.

Just now.

The roots have also grown more in the last 8 hours than in the last two days.

The problem is, I cant think of any way to accurately measure the PH of the mist itself with my gear. Thats going to leave me having to judge PH changes by looking at the plants rather than using any measurements. I hate that. It puts an automatic delay in judging changes, and add another level of guess work. I have not looked, but I doubt there are any sensors on the market that can measure the PH of micron sized droplets in real time. If there is, its got to be $$$.

By the way - these nozzles put out a nice circular hollow cone when clean.

Now that I know all this stuff, Im going to wait before I start the new C99 seed. I want to get the new filter installed, clean the system thoroughly, then see how the coverage works as the roots grow longer and wider on this unknown seed. I want to make sure I have the nozzles in a good position/angle that will work from start to finish. That should be a lot easier with a full cone of spray that is uniform in all directions.

As far as why the PH is doing what its doing - I have no way to test any of the possibilities that were brought up in the other Non-linear PH thread. I will discuss those things over there.

Boredom is pretty much 100% the cause of all my difficulties in life LOL. Got bored, got married, got bored, had a kid, got bored, traded a toyota in for a ford…

I will, however, probably be running a hempy bucket for comparison, to see just how much LITFA fits in one of those buckets…

I would stick with your plan to adjust the rez and not worry about runoff. Of course it reacts with air, but I would think that enough of the “virgin” solution is making it onto the roots to balance that out. I’d also try going up to 5.8-5.9 for a day, for the sake of varying the absorption of different good stuff.

2 Likes

hahahahahaha!!! I am right there with you buddy :smiley:

Yup, thats the plan. Well, almost. Im going to raise the PH sloooowly until I start to see issues again or the plants stop improving. That should give me a hi/low range to shoot for. Then I will let the rez go from low to hi but stay within those boundaries.

1 Like

Finding the upper boundary of acceptable pH is a great idea :+1:

1 Like

The torture subject, er, ah, the cute little orphaned seedling, continues to improve, but more slowly. There was a huge jump when I went from PH 4.9ish to 5.4ish. There was more improvement last night when I went up to 5.6ish, but not as much. Now Im up to 5.8. The changes are showing up within just 2 or three hours, but the smaller changes are harder to see. Ive been taking before/after pics to compare.

I must be getting closer to ‘good’ because the fuzzies started showing up again night, and today, there are a lot more!

The cleaned out nozzles have let me lower the timing to .5 sec ON and 45 seconds OFF for an even lower over all flow rate. My filter will be here tomorrow, I will clean everything out and see how that works.

In the thread on non-linear PH changes, we got off on a side track about the effects of hi voltage static charges on water droplets. That has my MacGyver going strong trying to think of ways to apply some of that info to HPA. I think I can hear that poor orphan seedling crying ‘Danger Will Robinson!’ already…

4 Likes

This should not be a big surprise to anyone, but the best PH for the rez is right around 5.7 to 5.8. Its amazing to me how quickly the plant responds to PH changes - both in how fast it starts looking bad and in how fast it recovers. It just takes a few hours to see big changes.

You can also tell by how well the roots are growing. Having the PH dialed in for the last 24 hours or so has allowed the roots to really take off. They have almost doubled in mass just since yesterday with lots of new fuzzies.

Here is how they looked yesterday.

And tonight.

The plant itself is also looking much better.

I got the new 200 mesh/80 micron filter installed. Hopefully that, along with running a sterile rez, and extra light proofing, will keep the nozzles clear.

I had been re-calculating flow rates each time I changed timing, so I could judge how big a change I was making in the flow rate, but that is tedious. I was about to set up a spread sheet to make it easier, but I realized all I need to know is the ratio of ON to OFF times.

For example, earlier in the grow, a setting of 0.7 sec ON and 55 sec OFF was working really well. That gave a flow rate of right at .6 gallons per day.

So, if you divide the ON time by the OFF time, you get the ratio of on to off. As long as that number is the same, the flow rate should be the same - up to a point. At shorter on times, things get wonky. For my setup, 0.3 seconds ON is really the absolute minimum for a nice uniform spray, but it doesnt quite fill the chamber. 0.5 seconds is about the shortest I can go.

So, my original 0.7/55 = .0127. Any other on/off times that have the same ratio will have the same flow rate.

Having nice clean nozzles, and spending more time adjusting the position and angles, has let me get back down to 0.5 seconds of ON time. Im currently at 41 seconds of OFF time for a ratio of .0121. So Im running a little lower flow rate than before. The roots look good and are staying wet, but I will be checking them every couple of hours for a while to be sure this is a good setting.

Im finally starting to feel like I have a handle on this. Of course, this is just the earliest stages of growing, so we will see.

Im going to let this victim, er ah, poor baby go for a few more days, or maybe even a week or more so I can judge how th roots do as they get larger and spread out. I may need to play with nozzle positions some more once the roots start to reach the lower portions of the chamber.

Once Im happy with that, I will start my C99 seed and grow for real :slight_smile:

7 Likes

So happy for your roots! This is pretty awesome. 5.8 is where my dwc likes things too. You’ve put in a lot of effort, great to see it returned in a bundle of white fuzzy roots! :thumbsup:

2 Likes

I am reminded once again. that I have a serious condition. Very serious. I forget exactly what the medical name is, but its something like Havetomeddleosis, or Cantleaveitaloneitis, or maybe Mustfiddlewithit Syndrome. The main symptoms appear to get much worse when things are going well, and running smoothly - bad hives, nervous sweats muscle twitches, inability to sleep, cant sit still, mind racing, etc. This is compounded by another problem I have. I thought at first that I was allergic to LITFA, but now I wondering if maybe I just havent been taking enough.

The bottom line is, things have been running so well that there is absolutely nothing for me to do - and Im a nervous wreck! Its only been a little more than day, but still… :slight_smile:

The roots and the plant are doing great. The roots continue to grow rapidly with good horizontal spread, and nice white color, and best of all - lots of fuzzies! They have spread out to the sides enough that I can no longer easily get the net pot out of the hole without damaging the roots.

Trying to get good clear shots of the roots while they are in the chamber is not easy - partly because there isnt much contrast on pure white roots, but also because the mist hangs around a good while now that Im running such short OFF times, and it leaves droplets on the lens or just fogs up the image. I tried sticking my USB cam in through the hatch I made in the side of the root chamber, but I have a hard time holding it steady enough to get a clear shot.

There seems to be lots of fuzz in the middle and upper portions of the root mass, and deeper inside, but the ones hanging down are mostly smooth.

I think thats because those longer hanging ones tend to collect, and channel the runnoff from the higher ones, which keeps them too wet. Those drops that collect, and sit on the ends, make the root want to keep growing down, so thats the direction they go. The upper ones seem to be getting more of the ideal wetness, and/or droplet sizes, so they grow sideways - towards the source of the mist - and form more fuzzies.

I have been watching the larger droplets that collect on the roots to judge when to increase or lower the off times, but if I try to get rid of all the hanging droplets, the other roots want to dry out. I think that means that the system is still not really ideal as far as droplet distribution, and size, but I think Im for sure in the ball park.

Now, if I can just not screw it up… :smiley:

6 Likes

:laughing:

Looking lovely. Brilliant work. How are the leaves looking?

Oh man this a tough one for intervention, though. Even after a massive dose of LIFTA, you are still having withdrawals. Overgrow, this is a call for help! Give this man some sort of distraction.

Uh oh. Are we too late?

1 Like

Leaves look pretty good. The plant has recovered from my earlier PH screw-up nicely for the most part. I have some slight drooping of the tips of some of them that showed up today. I suspect that is because I re-did a chlorine treatment late last night. Im going to hold off on any more chlorine for a while or maybe just go with a smaller dose - maybe 1PPM.

These are all lights ON pics, so the leaves are not really that pale.

Your Jacobs Ladder pic is actually kind of appropriate. I have been thinking seriously about ways to get a static charge into the root chamber - safely.

After watching those videos you posted in the non-linear PH thread, showing hi-voltage, and static effects on droplets and even streams of water, I cant help but think it might have some application in HPA - IF - there is a safe way to do it. Im talking safe for the plant mainly.

This one was most interesting to me. If a simple, low power static charge can effect a stream of water this dramatically, then moving some micron sized mist should be even easier.

I plan to try that trick, but using nute water. Im curious to see if water with ionizing salts dissolved in it behaves the same way. Im pretty sure it will. A static charge is different from the charge created in a solution by ionization of the dissolved minerals. That video looks to me like its the Lenard Effect creating static charges on the stream, which is in turn bent by the static charge on the balloon.

The problems Im anticipating are mainly in two areas.

  1. What effect will a static charge have on the roots and the plant? I need to Google that to see if there is any data out there.

  2. If that looks safe, the next problem is that nute water is pretty conductive. Every surface in the root chamber will have a fine layer of salty water on it. Im afraid that will just ground any static charge before it can build up.

There is also the potential issue of electrolysis. That should only effect the nozzles, but if the current is super low, it shouldnt be much of a worry - if at all.

There is also the potential of creating hydrogen and oxygen gas in the chamber. The risk is that any that is produced will be in the perfect explosive ratio. But, I dont think that will be a serious concern - if - the current levels are low enough.

This should be easy to test once I get a good, low power static source figured out. Not sure when I will get around to that though.

Assuming the droplets are negatively charged, the plan is to - somehow - charge the top of the root chamber positively and see what happens. I havent come up with a good way to do that though - yet. :slight_smile:

Frankenstein roots anyone :smiley:

3 Likes

I dig this idea. If you find a way to powder-coat your roots, and roots only, with a nutrient solution of proper aeration, I will be the first one to attempt to license that patent for non-commercial use :slight_smile:

Seriously though, awesome.

2 Likes

Didn’t even think of this, that would be a good reference/technique(s) to review. Macro scale, open/mixed environment, conductive/“wet” materials, targeted deposition.

2 Likes