passive plant killer
- Thread starter delta9nxs
- Start date
JJ, it will work like that but you will not get the o2 from the sidewall "air" holes. all of your o2 would have to come into the medium from the top. no "plunger effect".
another consideration, should you desire at some point in the future to install a pulse watering system using a pump you need enough depth for the pump to operate in yet still maintain a 3" air gap. this leaves you a 3" water level. hard to operate a decent sized pump in 3". the only way around this would be to have your pump bucket recessed into a hole in the floor.
now i understand why your coco doesn't fall out. the tailpiece is almost in contact with the bottom of the outer bucket.
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First of all, that's WAA:AAyY too complic8ted.
2nd, where are you supposed to poop?
3rd - do the buketz hafta be black?
4th - if you really want to increase 02, why not ramp up the (oxygenated) water-flow? There is no such thing as over-watering, only under-oxygenating. (stolen from GratefulHead).
hey, man! aerating the water will have a minimum effect on the plants as the flow of water is not very great and the entire system is "slo-mo-hydro".
you also cross over into the area of needing to maintain water temps in a certain range just to maintain o2 content. chillers and/or heaters. the ppk negates the use of heaters and chillers.
a better solution would be to aerate the medium instead.
but really, the pulsed irrigation used with the side air holes acts like a big slo-mo air pump every time it fires. using the 21% o2 available from the atmosphere.
darth, it would be nice if your friends would join us and give their impressions of the system.
hi, zeke99!
actually, i have come to believe that the mechanical properties of a medium are far more important than the medium itself. the plant i pictured above is the first plant in a mix of coco, rice hulls, and turface.
i played around with the mix until i got about 35% air porosity. the plant looks pretty good for 3.5 weeks.
some substances with a high silica content, such as turface and rice hulls, seem to have a prophylactic effect on root diseases.
other than that, i don't think it makes a great deal of difference what you use as long as it maintains structural integrity for the course of the grow.
i'm not real fond of peat in hydro as it decomposes rapidly. this decomposition collapses the cellular structure, changing the mechanical properties as it does so.
it also requires corrective measures to control it's influence on ph. peat drives ph down. the dolomitic limestone is in your mix to counter this tendency. this is a recirculating system so i feel the limestone will interact with nutrients over the life of the plant.
i don't understand your last question about "after construction".
if you intend to hand water the top for a while build it so that you can add the pulse system later. it makes a huge difference.
d9
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it would not be a good choice to amend coco if used alone. i used it to prevent the rice hulls from compacting. it is also there as a replacement for some of the too fine botanicare coco. used 1 part in 5 it only brings bulk density up slightly. maybe just enough to hold a plant better.
also, JJ, i've been meaning to tell you that my humidity has now gone back up to around 55-60 % and i have raised tds to ec 1.5 or 750 ppm at .5.
this is easily achieved with jack's using 450 ppm jack's and 300 ppm calcinit or ec .9 and ec .6.
later, dude!
and finally, last but not least, IF.
couscous? gerbils? OMFG!
couscous amended with oatmeal and mashed potatoes?
and gerbils? if it turns out you actually own gerbils i'm going to have to cancel that dinner date, i'm not into gerbils or should i say they are not into me!
why is it that gerbils in pet stores all have that terrified look on their faces and nervous tics. have they heard rumors about the "end"?
your homework for the day is to study the effects of pulse duration and frequency on nutrient uptake and o2 assimilation.
d9
couscous? gerbils? OMFG!
couscous amended with oatmeal and mashed potatoes?
and gerbils? if it turns out you actually own gerbils i'm going to have to cancel that dinner date, i'm not into gerbils or should i say they are not into me!
why is it that gerbils in pet stores all have that terrified look on their faces and nervous tics. have they heard rumors about the "end"?
your homework for the day is to study the effects of pulse duration and frequency on nutrient uptake and o2 assimilation.
d9
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zeke99
Active member
thanks for the info. on the medium. Maybe I'm stuck for now not being able to use the PPK because of the lack of good coco locally. I'm not paying shipping or driving two hours each way for bags....
But for future reference:
What method do you use to test for porosity? A link will do just fine. There are a few out there, but you seem to know what you're talking about.
What I meant by the 2nd question, is if I build one or two PPKs with the intention of hand watering, what exactly do you do after the initial planting? The top bucket is detachable by your design, so do you just manually fill the bottom reservoir and than proceed by keeping an eye on the level?
zeke, what you are talking about is operating it like an improved "hempy". i did that in the first part of the thread.
this will work fine if used correctly.
build the top bucket as i do now. build the bottom bucket the same except no tire valve. instead drill a small (7/16, 3/8) hole in the side of the bottom bucket 3" down from the top. water daily until you get a slight run-off from the hole. the idea is to keep the water level in the bottom container as stable as possible with frequent top watering.
this is drain to waste so you will need a tray under everything to catch overflow. if you let just a little run off occur it will evaporate between watering.
this method may be the best way for you using the peat mix until you can find an alternative. everything stays contained in the medium or the bottom container. there will be a lot of upward flow through the wick using this option.
IF posted a link to the porosity test a few pages back. it is also posted in the first page or two of this thread.
start looking for pine bark in your area. wheat straw, rice husks, ground corn cobs. turface or perlite would be good with these things. let me know what you find and i will try to recommend a usable mix for you.
d9
zeke99
Active member
https://www.icmag.com/ic/showthread.php?t=47837
Did you ever read that thread? Confirmation.
post 73
post 74
my whole system is up off the ground so my control bucket can be a bit low to hold more water, this also lets me grab a bucket full of solution when I want to have some runoff
hey, zeke, that quote is not mine. it is JJ's. i quoted it by hand from another of his post.
i am not that delta9
editing to say that i understand what you mean now.
the quote you attributed to me is JJ's.
and i basically agree with shroom's statement.
i'm also an old fish keeper and have built large concrete and epoxy systems for marine specimens. air bubbles themselves do not put much o2 into solution. it is the breaking of the surface tension that picks up o2. you can do it with a pump or a paddle wheel. i've seen huge catfish ponds being aerated with paddle wheels driven by tractor pto's.
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Are you assuming the plunger effect you speak of is significant? It may not be. It seems that it would be hard to measure.
Hey, JJ, I try to not make many “assumptions”. I agree with you that it would be hard to measure, but it is easy to observe the results. I am firmly convinced that I grew bigger and healthier plants when I began playing with “root pruning” holes.
For years I grew in containers without any sidewall holes. In the first part of this thread I was using un-drilled containers.
The literature is full of statements about how watering plants moves gases around in the root zone.
We are trying to introduce o2 and expel co2. In a non-standard growing container, one that we modify for growing weed, there are no holes pre-formed into the bottom for drainage and gas exchange. Almost all nursery pots have some sort of hole configuration. We have to make all the holes ourselves.
In a ppk, with the tail piece in solution in the bottom container, the only way for gas to move into and out of an un-drilled container is through the top of the medium. This may “work” but is not ideal.
In the coco forum you hear a lot about the “soggy wet mass” that occurs in the bottom dead center of the container. In my containers this does not occur. I can only attribute this to better gas exchange.
You used the term “significant”. I believe any improvement is significant. If it helps just a little it is significant. This entire thread is about the results of a series of “small” changes that have now added up to produce huge plants.
But back to the subject at hand. In physics the term heterogeneity is used to describe something that has more than one phase. Such as water (solid, liquid, and gas). For our applications water exhibits two of those phases, liquid and gas.
When the pulsed irrigation hits the top of the medium it is in liquid form. Because it is going into a medium that is already wet (vapor) it spreads (hysteresis) and falls (gravitational flow potential) in liquid form.
This falling, spreading column of liquid water travels in wave form through the medium until it reaches the wick, where it continues out of the grow container and into the reservoir below.
In between pulses the water content of the medium reverts to gas vapor form.
So when I use the term “plunger” I am trying to describe this movement. There can be no doubt that this movement is both pushing and pulling gases as it falls. The theory of displacement also comes into play here. Liquid water is not compressible.
The sidewall holes just add an additional capability to move gas by allowing some expulsion on the down stroke and intake as it passes. Sure can't hurt anything.
Someone said that plants grow best when the roots are sitting in a warm, nutrient rich fog. Well, o2 is one of the most used nutrients.
D9
sorry to hear that! come back when you can. later on, d9
I use smart pots which are all open to air, and they seem to perform equal to plastic pots (with bottom holes). It is hard to say why this is and I'm open to considering in certain environments smart pots would do better, I just haven't seen that yet.
I'm not sure I understand. It sounds like you are saying the the water that is in the medium is in a vapor state. Are you saying there is vapor in their with the water, I mean it is not just vapor.
I'm not sure I understand. It sounds like you are saying the the water that is in the medium is in a vapor state. Are you saying there is vapor in their with the water, I mean it is not just vapor.
