First time hydro, going to try Ebb/Flow - is this a reasonable plan?

Cold$moke

Well-Known Member
I still dont know if the added layer would merit too much though

Because with a ball valve you can make the film of water as thin as the batting .. Correct? Thus turning it into a "thin layer nft"

I beleive the idea of the whole thing is that the batting allows for the waters suface tension to maintain thin film

But this is all theroy to me at this point :)
 

Budley Doright

Well-Known Member
When you guys start these you should do a co-thread :). The reason I did the matt thing was to use a better media for beanies and to try and keep roots out of what little water was left after a flood. I didn't notice a huge difference with or without. One possible good thing in a drain to waste would be less water. I used spreader mat for NFT.
 

Larry3215

Well-Known Member
Ive had the roll of what I think is Dacron fabric sitting in a back corner of my hobby room for at least a decade, and I cant really remember where I got it or if its Dacron for sure. I decided Id better test my 'Dacron' cloth to be sure it really did have decent capillary action and could wick water.

I filled a mason jar to the brim with tap water and placed a small piece of the Dacron on top, and screwed on the lid, trying not to trap any air. I put a short piece of cardboard tube resting on the fabric and it quickly started to wick up water. A short time later I noticed water was also wicking out from under the cap and down the sides of the jar making a nice puddle on my work bench. So its wicking sideways along the grain of the fabric and through it.

I think it will work just fine as a membrane.

Im so tempted to pop one of my spare seeds and get started....
 

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Cold$moke

Well-Known Member
Im flipping sometime in a week or so

So i got a bit to plan and gather

Are you still going to use an airlift?
 

Cold$moke

Well-Known Member
I have plants that i poped in four inch blocks that will go in

They are going to be vegging for a while haha
I poped the seeds around Christmas so been going for a bit now :) but they are staying small since im a noob with rockwool which im fine with for now
 

Larry3215

Well-Known Member
Yeah, Im definitely going to keep the airlift pump. I dont see any need to buy a water pump and I dont really want to setup a gravity feed system. The first airlift I built can do up to 30-40 gals/hr which is way more than the MM technique needs, so I will probably have to slow it down.

Im also going to go ahead an aerate the rez, even though Andrew Parker says its unnecessary. I figure it cant hurt to have more aeration and my aquarium air pump has excess capacity.

Andrew Parker also mentions the need to provide air into the MM root chamber, but the only suggestion he has is having holes in the top cover. I dont want to do it that way because that means sucking in hot air from the grow tent. Im worried about that heat transferring to the rez water. Im going to hook my airpump's inlet side to the root chamber and make a path for air from under the grow tent to get inside. That will provide a stead flow of fresh, relatively cool, room temp air to the root chamber.

I didnt see any way to get fresh air into the roots in those videos with the mat/NFT technique in those videos either. I guess he is relying on the water being aerated enough? It seems like it would be a good idea to have fresh air to the roots too.

By the way, The technique Im going to do came with a cool name - membrane meniscus, or MM for short :)

We need a name for the technique your going to try. Since you're going to do it, you get to name it :) Got any ideas?
 

Larry3215

Well-Known Member
More on the Dacron for the membrane. I think what I have is actually something call peel ply thats used in fiberglass manufacturing as a release film. Ive done several searches for Dacron fabric, but all of it is the wrong type. Im mostly finding batting and very loosely woven fabrics - both of which are NOT what you want for the membrane. There is also sailcloth, but thats expensive and pretty heavy duty. Not sure how well it would work.

Dacron is just a name brand for polyester fabric, so I started looking for those.

Turns out that "fabric" shower curtains are made from the right stuff and seem to have a nice tight weave and smooth surface. Im sure Joan Fabrics or other fabric stores also carry similar fabrics you can buy by the yard for cheap. Heck, you may even have an old shirt in your closet that would work :) I think pretty much any tightly woven, somewhat shiny, slick, synthetic fabric would work fine - nylon, rayon, polyester, etc.
 

Larry3215

Well-Known Member
Oh - I got an email back from the guy who wrote that article in Maximum Yield mag. He is tracking down a copy of the book Andrew Parker wrote. I will share that when I get it.

I also asked him if he knew of any down sides or quirks, problems or issues with the MM technique. He says its just the normal hydro issues - light leaks to the rooting area, nute mixing, PH etc. He is still sold on it as being the 'next big thing' in hydro growing.
 

Cold$moke

Well-Known Member
Yup ill call mine meniscus membrane nft lol

I too will probably oxygenate the res just cause i have an alita running.my rdwc anyways.

And its just so ingrained to bubble the res although i might try it without .


I too have been working on a design to supply the root zone with fresh air i already have some parts ordered and waiting. Need a few more bits

Still working on the design for the table

Ie i dont know if i want a flat or ridged bottom

Both have merits and minuses in my head.

My biggest design issue is with the lid id rather make a reusable sturdy lid.

I will not rely on panda plastic for waterproofing

I might buy a commercially made tray but ill probably just build one out of wood

Plus im thinking of drainage designs and how to deliver a nice even sheet of water along the lenght of the cloth.

I think of it as a big version of nft nothing more

The main reason im so interested is i want to be able to simulate droughts towards the end of cycle to increase oils. And i see it being safer for water related root problems

Since water teansfers heat so well thats why eveyones rdwc runs warm.

But if the roots are always in a cool moist dark air chamber. I think they will be quite happy
 

Cold$moke

Well-Known Member
I dont know about being "the next big thing"

Hp aero is still the most efficient as far as water and nutrients but its just too finicky for me .

As i hated sprayers from my low pressure aero days enough lol

Yes i thought about adding.misters at one point too lol

Been thinking about this for the last 2 or 3 months

I just want it to be a ultra easy reliable and productive .

If it comes even close to rdwc as far as growth speed i will be sold. .. just for the simplicity
 

Larry3215

Well-Known Member
Yup ill call mine meniscus membrane nft lol
Wait! It just occured to me - there is no membrane or meniscus in that setup in the video, so you cant call it that! Sorry, couldnt resist :)

I think either one will do well. For me, I suspect any type of hydro will be better than growing in soil - unless of course, I screw it up royalyl!

How big is your setup going to be? My grow tent is just 7 sq ft, so Im limited.
 

Cold$moke

Well-Known Member
I thought they said the meniscus membrane is what the lens of waters surface tension is called?
Basically a drop of water has its own meniscus membrane? Mabey im ass backward

Edit to add
What is the meniscus of water?

A concave meniscus, which is what you normally will see, occurs when the molecules of the liquid are attracted to those of the container. This occurs withwater and a glass tube. A convex meniscus occurs when the molecules have a stronger attraction to each other than to the container, as with mercury and glass.Dec 2, 2016

A meniscus refers to the thickness or depth of a membrane of uncontained water and can be observed here as it moves from a horizontal to a vertical plane.
 
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Cold$moke

Well-Known Member
Ha, ill always know i told ya bout it though ;)

I have about 4x8 to work with mine
With the whole room being about 8x8

Mine will still be called. meniscus membrane nft
Which is the most practical name for it. ;)
 
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Cold$moke

Well-Known Member
I figure my table will be around 2.5 to 3 ft wide by about 6 feet long or so

Also in my head its really the same or close enough

In your system the dracon fabic keeps roots from sitting to deep in the nutrient film

In mine the bottom of the container will act much the same with just a thin film running through my capillary layer which after fills with roots will be mostly in the air with just the lowest ones actually wet

At least in theory
 
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Larry3215

Well-Known Member
Ah, your setup is much larger than mine.

Ok, I can see where you are coming from on the meniscus part, but not really with the membrane part. I guess its largely a matter of degree - and me being nit-picky/anal/pedantic :) I guess the biggest thing is the MM technique drastically reduces the amount of water actually touching the roots and therefor, the amount of water flow needed. As a side benefit, it also increases natural aeration. In your case, the membrane is actually just a way to hold water, where as in the MM technique the membrane keeps the roots way from the water and at the same time transports water to the roots via the meniscus/capillary effect rather than direct contact. There is a lot of overlap there for sure.

I just scored a copy of Andrews book! Havent finished reading through it yet, but so far its very interesting. He breaks down all the basic hydro types from an engineers viewpoint with details on why each is good and bad and how they work.

dang - its too big to up-load directly. I'll have to copy it to my Google drive acct.....
 
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