passive plant killer

[cactusjack]

Delta - Thought I'd let you know that the little 66 GPH pump (you are right, it really is more of a blower) isn't too big after all. At 17" of head rise I almost exceeded its capability. After feeding through a couple feet of 1/4" drip line and a handful of TEEs and elbows, the little pump delivers only about 9 oz of liquid during a one minute flow. Not too bad and I suspect I can live with that without changing feed frequency or doing any further work on flow restriction. I ended up with a set of TEEs for distribution similar to your approach. My WaterFarm type ring actually didn't do any better at distributing liquid and I think your approach is more predictable/repeatable

Ooooo! I like your idea for a "breathing" media due to pulling liquid out of the reservoir for top feeding. Sounds pretty neat and I guess I will get it for free with my setup. I'll put a piece of electrical tape over the vent hole and tape the joint between the buckets, but at this point its probably gilding the Lilly. This setup is already working so well that the slight benefit might not be noticed. Still, every little bit helps.

 

[delta9nxs]

cactus, thank you! the last three days i've been running 8 oz's every two hours just to see the effect. while it is too early to tell whether it will increase growth rate or not, i can say that it does not seem to be causing any over watering symptoms. so your 9 oz's might be fine. since you are stuck with the 9 oz's as a minimum i would suggest you play with the interval between events. 2,3, or 4 hours should get you what you want. when you pick up a handful of coco from the top and squeeze it you should get some water to just show between your fingers. this is right before the next watering event. if a lot of water runs out and drips off, it's too wet. this keeps o2 at a maximum level. you will notice the Atami stuff will show water between your fingers right out of the bag. i think that is what you want to maintain. they have to ship it moist for their nutrient pretreatment to work. I believe they do this to help resolve the initial cation exchange sequence. you can use it right out of the bag but i flush the hell out of it anyway to remove as much Na as possible and then re-treat it immediately with my nutes. i feel this is safer than allowing a potential conflict between different types of nutrients. also, never, at any point in the grow, let it dry past this point. this gives you a continuous hydraulic hook-up and movement in the medium.

another aspect of increasing overall top water volume whether it is derived from duration of event or frequency of interval, is that it should tend to bring your readings closer together. reducing the spread in numbers between your highest and lowest readings. this could have a beneficial effect on overall ph stability. this is, of course, if you run more than one res.

i think you can reach a point of diminishing returns with the top watering as you start saturating the medium. so a balance is called for.

I would like to know exactly what that timer you use is. Do you have a home depot item #? this could be important in the quest for a less expensive version.

later

 

[*mistress*]

(thanks JK!)
hydroponics nutrient management research.

 

[cactusjack]

Delta - The little timer I'm using is GE Model # 15089. HomeDepot SKU # 544158. Cost is $14.98. Their web site refers to it as an "in-wall" design. It's not. It is a little cube that plugs into a wall outlet. A nice compact design. One potential inconvenience with this model is that the single outlet is a two-pronger. It is polarized but has no ground. Kind of a pain since most pumps have a grounded plug.

For two dollars more ($16.98) they have another model with an identical timer but two grounded outlets. I haven't used it but I believe each outlet can be separately programmed. This one is GE Model # 15079. HomeDepot SKU # 545912.

 

[Carl Carlson]

For D9 ~ the rootball from a plant harvested two nights ago, grown in a 2 gallon round, 100% coco, hand watered, DTW.

 

[delta9nxs]

Mistress, I have that link and have read most of that whole site. It's excellent. Of course, the challenge is to remember it all and apply it. Sometimes i'll go into the next room to get something and then forget what it was. Thank you for putting the link up here. It should be read by everyone. Also, I wanted to tell you i'm going back to ph 5.2-5.4 input as I have not seen the mag problem on any other plant or on more than three leaves. It may have been a fluke. Who knows? The ph goes up from there anyway as soon as it enters the recirculating part of the system. This means no ph adjusters, so "appendix a" just got smaller.

Cactus, thank you!

Hey, Carl! That's a beautiful root ball. Pot roots love coco. But, don't you tire of drain to waste? For a while I had 56 3 gal hempy's going on the floor. By the time I finished watering with run off I was sloshing around in a deep puddle. I drilled drain holes through the slab so it would drain out, but what a mess. All over the world in commercial greenhouses and nurseries there is a concerted effort going on to convert drain to waste schemes to more conservative watering techniques. This is to conserve water and also try to stop as much of the nutrient salts from entering the water table as possible.

I've just finished the 8 oz's every 2 hours experiment and still don't know about growth rate but am satisfied that this volume doesn't saturate the medium. Now I am trying the same 96 oz per day volume but at 4 oz's per hour. I've taken two sets of readings and they show that the increased volume (96 oz) is modulating the spread on the ph readings. On 5-2 I had a low reading of 5.8 and a high of 6.3. yesterday it was 5.9-6.1. I'll do another set today. I would like to see the same effect on tds.

I got a chance to observe something really interesting last night. I now have 5 of the 9 in flower linked to a control bucket being fed from the same volume tank as the vegging plants. When the lights first fired up I went in to check everything and there was no drip from the float valve. About 15 minutes later there was a slow drip. At one hour it was 2-3 drips per second. I had just had a graphic demonstration of plants starting up the photosynthetic process.

Well, I took another hit and thought about it for a while and it occurred to me that this could be a way of quantifying the plants metabolic efficiency for a variety of reasons. You could measure the drip rate with brand new bulbs and then plot a curve over time to make a better decision about when to replace them, relative to themselves. You could compare nutrient programs, relative to each other. Effects of temp, rh, and ph on growth rate.

d9

 

[*mistress*]

that ph generally rises, & plantys seem to like acidic ph

this may help w/ calculating water requirements....

Physiology of Water Absorption and Transpiration

1/5-1/4 of the volume of the container, per 48hrs... whatever the container size is, usually enough water+fert...

5gal container
5*128=640

640/5=128
=1 gal water/solution every 48hrs (2 days).

or...

640/4=160
=1 1/4 gal water/solution per 48hrs...

that same amount can be applied daily, if that what gardener likey (64/80oz per day)...
64oz, or 80oz solution per day seem to get adequate run-off, yet not so much that it become un-manageable, or inter-fere w/ next solution application (usually next day)...
if the trough/run-off catch is fairly large volume, the water evaporates faster than it would in an individual bucket, or tote, etc...
basically, can run drain to waste w/out wasting any water/nutes, w/ measured watering & larger run-off basin... containers on basin floor, or slightly raised, no external bucket...larger volume of water buffers ph well

Water proof floor with pond liner

*edit*
?

container 1: 1 tsp/gal hyd. spec...
container 2: 1 tsp/gal c-nit...

adequate nutrient for entire season?

 

[delta9nxs]

Mistress, I did not have that ICT link and it's a keeper, thanks. I haven't read it all yet but will as soon as I can.

A lot of the big nurseries are building concrete catch ponds for containing run off. But i'm with you on this and prefer using as much as possible on the plants.

Mistress quote:
“btw, do you mix the hydroponic spec. w/ cal-nit, in same container? or, mix in separate containers & join when feed? 1tsp hyd. spec. give what ec? 2 tsp? ph, w/ tap?”

I don't mix in the volume tank as it always has some solution in it.

I mix in a 44 gal sterilite tub starting with a dry, clean tub.

I fill the tub with ro water from a big trash can used as a ro reserve via a hose, I have a quick disconnect on the water faucet I installed in the bottom of the drum.

Starting with an unknown volume of ro water I add jack's until I hit my target ppm, they recommend 630 ppm for commercial use. Mix it thoroughly. I use a canoe paddle. If you overshoot your target add water to bring it down before adding the calcinit. I usually give it about 10 minutes and then just throw in the calcium nitrate mixing after each application until I hit their recommended dose of 216 ppm. At this point your solution should read 846 if you are dead on. That's it. This will not precipitate.

“I've been playing around with the jack's 5-12-26, doing small mixing experiments. Their instructions show 2 mixing methods. The first shows using ½ tsp of 5-12-26 and ½ tsp of calcium nitrate in equal physical volume per gallon of water. I tried this several times and got 1014, 1016, and 1025 ppm at 5.0-5.2 ph. This at the .5 conversion.” Quote from me on post 354.

I should add that this is with ro.

What they are telling us here is that this also is an acceptable working strength. 1000 ppm. The higher concentration drives the initial ph down a little more. At 846 I get 5.2-5.4.

They are also telling us that you can run a slightly higher calcinit ratio. It won't hurt to throw in a little extra if you feel like it. Although those with tap water will probably need to cut back on the calcium.

For those without meters you could get the 846 from the equal parts method as 846 is approx. .85 of 1000. or 1000 is approx 1.18 times 846. so with this method you must know exact water volume and correct proportionally.

With meters it is easy to mix a balanced solution at any strength of jack's.

They recommend 846 as a starting point but say you want to run 900 ppm . I am now starting at 680 jacks instead of 630 so I need a corrected dose of calcinit. 1.18 times 216 is 234 and so on. 680 and 234 is 914. It's all just ratios.

d9

it occurred to me that i'm learning to play the xylemphloem.

 

[*mistress*]

it occurred to me that i'm learning to play the xylemphloem.

“I've been playing around with the jack's 5-12-26, doing small mixing experiments. Their instructions show 2 mixing methods. The first shows using ½ tsp of 5-12-26 and ½ tsp of calcium nitrate in equal physical volume per gallon of water. I tried this several times and got 1014, 1016, and 1025 ppm at 5.0-5.2 ph. This at the .5 conversion.” Quote from me on post 354.

target for imaginary gardner teehee... for re-post...

 

[Carl Carlson]

Hey, Carl! That's a beautiful root ball. Pot roots love coco. But, don't you tire of drain to waste?
By the time I finished watering with run off I was sloshing around in a deep puddle.

I've developed a simple and inexpensive system that separates and contains the waste, but it is still a waste. No way to avoid that. The only problem is everything that I build comes as a disaster first so transition to the PPK will be slow. Viva la Revolucion.

I got a chance to observe something really interesting last night. I now have 5 of the 9 in flower linked to a control bucket being fed from the same volume tank as the vegging plants. When the lights first fired up I went in to check everything and there was no drip from the float valve. About 15 minutes later there was a slow drip. At one hour it was 2-3 drips per second. I had just had a graphic demonstration of plants starting up the photosynthetic process.

It's basically the coolest grow related thing I've ever heard. I knew that it took some time for plants to start the process, but your observation in that way is awesome.

Well, I took another hit and thought about it for a while and it occurred to me that this could be a way of quantifying the plants metabolic efficiency for a variety of reasons. You could measure the drip rate with brand new bulbs and then plot a curve over time to make a better decision about when to replace them, relative to themselves. You could compare nutrient programs, relative to each other. Effects of temp, rh, and ph on growth rate.

d9

good stuff, especially the bulbs, that's real world applicable right now.

 

[delta9nxs]

hey, carl! thank you!

on the drain to waste thing. i have done a lot of it. and the worst kind, which is just running it out on the ground. it's inevitable with any form of agriculture. some drain to waste and run off has to occur and for years, probably since around 1930, it was the accepted norm. in the last 20 years it has become an issue with the public water supply. they are finding high concentrations of the elements found in fertilizers in the water being treated for drinking and bathing in some areas. i won't drink my tap water. it tests between 200-360 ppm depending on season. it's full of something other than h2o. they got real tense down at the water company when i walked in and asked them for a lab report. then they gave me a statement printed on glossy paper with birds and butterflies and trees and smiling people, fish leaping out of the water, you know the type, that said basically that they had complied with federal epa requirements and that the water wouldn't kill me. never did get that lab report.

But really, us small indoor growers are probably the least significant group of offenders. It's the big ag companies that are doing it the worst and resisting change the most. It's just that it's now the time for all of us to change. We are all in transition.

 

[cactusjack]

Delta - Regarding your drip tracking to monitor plant metabolism... pretty neat! At first I thought that it wouldn't be very useful because the size of the plant is always changing along with its water needs. Then I remembered you are running a perpetual grow and you have a significant number of plants in all stages of flower. All things being equal, they should average out the same on a week to week basis so monitoring drip may actually be useful as an indicator of changing metabolism. Very cool! I guess a caveat is that the room temperature and humidity should also be relatively constant on a week to week average basis. Otherwise, changes in evaporation might skew the results.

Interesting. At 96 oz/day going in the top, it sounds like you are approaching the daily use of the plant if not sometimes exceeding it. Since the wick draws off excess and prevents a perched water table, you can probably flow considerably in excess of the plants needs without saturating the media. Maybe its true what the say about coco. You can't over water it... as long as you have a wick pulling away the excess so there is no perched water table.

This presents the possibility that you are running with negligible bottom feed. Just a bit of re-absorption between feeding pulses. Intellectually (only so many things I can build at once) I'm curious at this point in a top feed only approach for a ppk-like device (sort of the *mistress* approach?) since I think I have an unusual way to implement it. I'll noodle on it for a couple days, then sketch it up.

 

[delta9nxs]

Hey, cactus!

To actually use the drip rate that way would take more knowledge of math than I possess. You would have to make multiple math models that factored in everything we have mentioned and probably a lot more.

At 4 oz's per hour the drip still runs from the volume tank more than 30 minutes each hour.. Which indicates that the sub system is moving water upward during that time since there is no top feeding going on. I think each watering acts like a wave in the medium, with an almost equal amount of water being displaced rather rapidly towards the res. Within 15 minutes of each event the system has equalized and flow reverses.

If you are going to install a wick/sump why not build it so it feeds too? Really just as easy and probably more effective at controlling salt build up.

The combination of the two feeds does something in the medium that either one alone does not. I have no way of measuring it but I think that it has to do with the wetted profile, the pulse/wave motion, and a moving point of equilibrium. There are no dead spots. Oxygen is obviously getting to the bottom center, where people are reporting the soggy mass. My readings indicate no salt accumulation. There is a lot of subtle movement going on. Like an ultra slow underground river.

Remember the hysteresis paper? Water moves into a wet area easier and faster than a dry area, creating a wider wetted front. This is cohesion at work again. Water has a stronger attraction to itself than to other substances. It naturally wants to channel in a dry medium.

With bottom feed alone salts tend to accumulate in the top of the medium. With top feed the opposite is true. I'm getting none whatsoever. So there is another dynamic at work.

Ph will be more stable in the medium with the combined feed because of no salt build up.

Also, in flower, during the dark phase, the sub-irrigation is still at work, keeping the roots in a constant state from a chemical and ph standpoint.

And, in the event of a power or pump failure your plants will still be alive after that long weekend at the beach.

d9

 

[iSMOKE.KUSH]

Read through most of this thread...

a few things. i was wondering if you could show me the post where you advocate 20/4 veg.

also...i use pure pro mix bx hempy style in my grows. i hand water usually every other day.
i run a schedule of heavy feed , light feed , no feed , repeat etc etc..to avoid salt build up.

i know exactly how much to water just enough to not get any runoff but also saturate the root zone...

i have a 10,000 watt sealed room with co2 scrog style.

i'm just wondering what you think of my style..this is how i have grown for years and usually pull down 2 pounds a light..i love the way you break stuff down, but i'm super stuck in my ways because they work yunno...

i just wanted to get your input on my system and why it works..i just know how to make it work not why.

 

[turbolaser4528]

hey, turbohead! wassup, my brother?

i've been doing a lot of reading on air pruning, looking at the various methods and reasons. there are at least 30 examples of containers designed to achieve this shown in the commercial and scientific literature, and the patents and applications, and i've been thinking that the reason that there are so many extremely diverse methods of doing it is that with each variation comes the possibility of getting a protected patent. it's all about $$$$$$. mine cost 2.34 at lowes for the bucket and 10 min. with a 5/16th bit.

later

nada man, just trying to find my way through the concrete jungle to see if there's anything on the other side. whats up with you mayne?

I went with plastic, glad i did, not paying 5$ a piece for smart pots. Just have to find my drill haha l8r

 

[delta9nxs]

hey, ismoke.kush! welcome!

i'll have to find my info on 20/4. i don't have time tonight but i'll get back to you on it.

there are many ways to grow, the plant is very adaptable to very diverse methods.

what you are doing is called "steering". it is an almost intuitive ability acquired after years of gardening. you are obviously very good at it.

you know your environment, your plants, and your medium. i would be wary of your medium because i have no experience with it. i'm very good with turface and perlite, and am getting there now with coco.

i can take a reading and adjust input to control the direction of tds and ph trends. my corrections are usually right but i'm just using years of experience, not math.

most new growers can't do this.

there is no "bad" way, or "best way" to grow. it is what works for you based on your lifestyle, that really matters. this is not a competition. i love seeing people grow any way they do it.

at 2 lb's per light i wouldn't make any sudden changes.

what i'm trying to do is develop something that is almost automatic once set up. that is so stable that it can be used without meters or much plant knowledge. this is still very experimental but it seems to be working great. i know i'm growing the best plants i've ever grown in it.

thanks for dropping by and feel free to ask anything or offer suggestions, this is a wide open thread. i don't even care if it's on topic or not. i just like talking about growing cannabis. i'll try to dig up what i've got on the 20/4 schedule but i bet some other folks here might have some input too.

later on, d9

 

[*mistress*]

........

 

[Carl Carlson]

20/4

http://www.icmag.com/ic/showthread.php?p=3249486&highlight=20/4#post3249486

Introducing “Hydraulic Redistribution”.

Hydraulic redistribution can only occur during the “dark” or “lights off” phase. It can therefore be used as a management tool to manipulate the upper medium moisture content.




it's one of the most important posts on the thread.

 

[cactusjack]

Delta - Although I'm pretty happy with a 100% bottom feed approach, the top feed kit keeps kicking around in my head. I can't help myself. I'm a hardware junkie. Admittedly the top feed kit is pretty simple, but at some point even simple designs start looking complicated to me so I like to stand back and try to "simplificate".

Attached is a cartoon of an approach that I've been noodling on. It depends on a float valve design that doesn't exit to my knowledge, but I think I can solve that problem. Till then, keep in mind that the float valve does not dump into the volume where the control float resides like a conventional float valve. Instead, the valve output is led up to the top of the media where it provides top irrigation.

The idea is to introduce fresh solution into the system at the top, but then wick the runoff back up into the media between top feed cycles. The top irrigation continues till the float senses enough runoff to close the valve. After that, liquid wicks back up until the float opens again and the process repeats.

I won't know how well it works till I build one since the living plant is an integral part of the system. A timing problem could result from the lag between flow entering the media and flow exiting into the bottom reservoir. It could result in a lot of liquid continuing to enter the reservoir after the valve is closed. This could potentially result in too long of an interval before the valve reopens. A possible way to avoid this is to have a relatively low flow rate so as to minimize the quantity of liquid still in transit through the media when the valve closes.

I have two valve approaches at this point. One is a simple float driven pinch valve (still conceptual), the other has no moving parts and has actually been tested. Any thoughts on how the plant might respond to such a setup?

 

[delta9nxs]

Mistress, ….....!

carl, thank you!

Ismoke.kush, that is the post where I decided to go to a dark period after 9 years of 24/0. it explains why I switched but does not show the research paper that showed the best plant response at 20/4. i'm still looking. I've got it somewhere. But also in the forums here a few folks have reported good results with 20/4 as opposed to 18/6, 22/2, and 24/0.

and now, cactus freakin jack! Damn you! I was thinking I was going to get a good nights sleep tonight, but you had to royally screw that up. You are a freak of nature! What an idea!

I can see this working but without the strong pulse/wave effect. But you would definitely get a replacement flow. No one yet knows what effect the difference between the two might be to the plants and there is only one way to find out. i think it will grow weed.

The mechanical problem was warping me for a while but then I took another hit and got a flash. I got an idea about the mechanical problem at the same time. Then the flash went away. But I still got the idea.

In your drawing you show the feed line from the volume tank going down to the float position. Instead make it go to the top rim of the media bucket plumbed to a lever actuated valve mounted on the rim. The lever or valve could pivot on the rim. It should be connected by a vertical rod to a float that has no valve which has been mounted in the usual position in the res. The float itself should also be on a lever. This lever should pivot in the same fashion as the valve lever through a waterproof or rather air proof opening in the sidewall of the reservoir bucket, actuating the vertical push rod. That lever actuated valve could be the standard float valve without the float. The float itself could then be mounted to the lower lever.

I think I might have another way of doing it but it's not fully formed. I keep thinking about the way a toilet flapper valve works but i'm having trouble hooking it up.

Revenge is sweet!

d9

editing to say that this approach could work with a single plant but i think it would be much more difficult to arrange with multiple reservoirs.