New oxygen technology in RDWC DWC pot grows

Do you believe "low oxygen"events causes fungal outbreaks in RDWC DWC?


  • Total voters
    29

J Henry

Active Member
Garden & Greenhouse Product Review - The O2 Grow Unit http://gardenandgreenhouse.net/index.php/products-mainmenu-22/108-product-profiles/2078-garden-greenhouse-product-review-the-o2-grow-unit Anybody here using this new oxygen technology in RDWC DWC pot grows today? If so, how’s this working for you.

Type A grower prevents fungal outbreaks. Type B grower’s waits patiently for the root rot and just accepts it, then treat the disease outbreak when symptoms present?

Many/most RDWC DWC pot growers practice crisis intervention (treatment with chemicals) routinely when it comes to fungi and root rot diseases. It’s common and customary to wait till symptoms appear, brown slime fungus on the roots, you know the symptoms and the routine… the race is on to save the crop. Waiting and watching for the rot symptoms causes some growers a little angst, other growers know it’s coming and have the chemicals and teas on standby ready to roll, these are the growers that prefer to treat the disease vs. prevent the disease Growers always have a choice, the treatment or prevention.

“They” say that Pythium and other fungal pathogens are opportunist, they are ubiquitous and wait patiently for the right opportunity in nutrient solutions and root zones. “They” also say that the right opportunity is a “low oxygen” event.

“They” also say that preventing a “low oxygen” prevents any opportunity for a fungal disease outbreak.
 

Psyphish

Well-Known Member
I stopped growing in hydro because I got root rot every time, I couldn't keep the reservoir temperatures low enough in my tent. I even added H2O2 every time, but it wasn't enough, chlorine might've worked though.
 

J Henry

Active Member
Etiology and epidemiology of Pythium root rot in hydroponic crops: current knowledge and perspectives

John Clifford SuttonI, *; Coralie Rachelle SopherI; Tony Nathaniel Owen-GoingI; Weizhong LiuI; Bernard GrodzinskiI; John Christopher HallI; Ruth Linda BenchimolII

IDepartment of Environmental Biology, University of Guelph, Guelph, ON, Canada, N1G 2W1
IIEmbrapa Amazônia Oriental, Caixa Postal 48, 66017-970, Belém, PA, Brasil http://www.scielo.br/scielo.php?pid=s0100-54052006000400001&script=sci_arttext

Concentration of dissolved oxygen in the nutrient solution is a critical factor influencing root rot and crop productivity (14, 38, 88, 120). In general, root rot increases when oxygen levels are low (14).

Gases move to and from roots of plants in many types of hydroponic systems chiefly by mass flow of gas dissolved in moving solution, which contrasts with diffusion through gas-filled pores as occurs in soils. [Air] Oxygen concentration in the root zone of hydroponic crops is commonly 6 to 8% (123) and growers have been encouraged to maintain a minimum of 5 mg oxygen L-1 nutrient solution (36). Concentration of dissolved oxygen can quickly decline, however, especially when temperature of the nutrient solution is high. In the absence of biological factors, the level of dissolved oxygen in water declines, for example, from about 9 to 7 mgL-1 as temperature increases from 20 to 35ºC at 101.3 kPa and 100% relative humidity. Of greater importance, however, is greatly increased demand for oxygen by roots and root-zone microbes as temperature increases, factors that become particularly important when crops have produced dense masses of roots and when microbial populations are high.

It has been further estimated that a crop that is environmentally stressed requires about ten times more oxygen than one not under stress (39, 94). While allowing the nutrient solution to free fall back into the nutrient recharge tank helps to maintain adequate oxygen levels, injection of oxygen directly into the solution may be needed, especially in continuously recirculating systems.

Oxygenation is one of the few practical measures available to growers when root rot is well advanced, and helps to avoid further necrosis, disintegration, and sliminess of the roots (39).

*** The observations of Chérif et al. (14) suggest that elevated levels (e.g. 11-14%) of oxygen would be advantageous in protecting roots and promoting crop productivity.

*** Air/aeration is 20% oxygen - Oxygen concentration in the root zone of hydroponic crops is commonly only 6 to 8% or about 5 ppm DO concentration with mechanical aeration --- 11-14% of oxygen would be advantageous in protecting roots and promoting crop productivity. This would require supplemental oxygen in order to continuously sustain an oxygen rich environment (24% oxygen) or greater using supplemental oxygen. Air will not meet this oxygen requirement regardless of the volume of air pumped and bubbled into the water or flumed into the air.

Hydroponic systems are often extraordinarily conducive to root rot epidemics in part because the root zones lack communities of microbes that can effectively antagonize pathogenic species of Pythium associated with the roots, rooting media, and nutrient solution.

Technologies to facilitate tracking of Pythium spp. and root disease are an obvious step in optimizing effectiveness of root-zone treatments such as use of microbial agents and oxygenation of the nutrient solution, as well as other measures to control root rot.

Data banks of dissolved oxygen levels and temperature of the nutrient solution in relation to important variables such as Pythium, microbial agents, other microflora, root rot, and crop growth and productivity are needed to develop protocols for their rational use and to adequately understand the value of such use.

*** Root rot fungi do not discriminate between plant species or root zones, any “low oxygen” presents an excellent opportunity in any DWC RDWC whether it a pot grow or a tomato grow. So these researchers claim, this is their story and they are sticking with it.
 

rkymtnman

Well-Known Member
<snippet taken from the link in the OP>
"The O2 Grow emitters will help achieve the maximum amount of dissolved oxygen that the water can hold in a shorter amount of time that air stone."

Anyone see the sneaky wording?
yep! he's trying to sell a $1000 oxygen concentrator that you can find used on craigslist for $200. and he has yet to offer any proof that it even works.

if you look at the high times review of his product, towards the end it says "increased levels of DO may or may not be helpful" to plants. wow!! that's a really glowing review huh???

j henry is a charlatan, a thief and a loser. all rolled into one big steaming pile in my opinion.
 

J Henry

Active Member
"The O2 Grow emitters will help achieve the maximum amount of dissolved oxygen that the water can hold in a shorter amount of time that air stone."

Anyone see the sneaky wording?
You might want to rethink “sneaky wording.” There’s no “sneaky wording” at all, electrolysis of water is the decomposition of water (H2O) into oxygen (O2) and hydrogen gas (H2) due to an electric current being passed through the water. This technology has been around over 200 years. 100% pure oxygen is the maximum amount of oxygen possible, air has only 20% oxygen if you pump a little or a lot, doesn’t matter. No “sneaky wording” here. You just read it wrong or missed the point, that’s all.

Check it out, see how and why this works: https://en.wikipedia.org/wiki/Electrolysis_of_water

Maybe this wording is easier to understand… There’s a huge difference between air and pure oxygen. Air is 20% oxygen. Emitters make pure 100% oxygen. Nothing sneaky here, just science and old technology to fix “low oxygen” problems caused by air and aerators and failure to oxygenate safely. There’s nothing sneaky between 100% O2 - 20% O2 = 80% O2. Tomorrow, next year and a decade in the future that answer will still be the same.
 

J Henry

Active Member
Maybe if we are stuck on Mars like Matt Damon in The Martian we will hit you up for your space age technology. Back here on planet Earth there are more efficient ways to add O2 to water and max out DO.
Here's something stimulating and interesting about understanding dissolved oxygen. How about 300% DO Supersaturation here and now in RDWC DWC pot grows?

Understanding Dissolved Oxygen by Kurt Becker

GrowerTalks Magazine Monday April 11, 2016 Published 1/29/2016 http://www.ballpublishing.com/GrowerTalks/ViewArticle.aspx?articleid=22058

This is a little step up in the world of oxygenation, what you think about this higher tech stuff?
 

redi jedi

Well-Known Member
Here's something stimulating and interesting about understanding dissolved oxygen. How about 300% DO Supersaturation here and now in RDWC DWC pot grows?

Understanding Dissolved Oxygen by Kurt Becker

GrowerTalks Magazine Monday April 11, 2016 Published 1/29/2016 http://www.ballpublishing.com/GrowerTalks/ViewArticle.aspx?articleid=22058

This is a little step up in the world of oxygenation, what you think about this higher tech stuff?
Copied from the link you posted...guess you didnt read it?..lol

Improving levels of dissolved oxygen can be done through various methods. Simple aeration or agitation can increase dissolved oxygen enough to prevent problems. Injecting air or, especially, pure oxygen can increase levels as well, but only as high as saturation levels. Paying attention to temperature can also help improve DO, as colder water can hold more oxygen. Additionally, water at atmospheric pressure will hold less oxygen than when under pressure. Think of a bottle of carbonated water: while under pressure, the water holds more carbon dioxide than it can when the cap is removed and the pressure is released. Once the bottle is opened, the CO2 begins to gas-off from the water, effervescing. The same is true with oxygen. Adding oxygen to a pressurized system can increase the level of DO.

So much for super-saturation...
 

WeedFreak78

Well-Known Member
Copied from the link you posted...guess you didnt read it?..lol

Improving levels of dissolved oxygen can be done through various methods. Simple aeration or agitation can increase dissolved oxygen enough to prevent problems. Injecting air or, especially, pure oxygen can increase levels as well, but only as high as saturation levels. Paying attention to temperature can also help improve DO, as colder water can hold more oxygen. Additionally, water at atmospheric pressure will hold less oxygen than when under pressure. Think of a bottle of carbonated water: while under pressure, the water holds more carbon dioxide than it can when the cap is removed and the pressure is released. Once the bottle is opened, the CO2 begins to gas-off from the water, effervescing. The same is true with oxygen. Adding oxygen to a pressurized system can increase the level of DO.

So much for super-saturation...
But Henry's Law and FiO2!
 

J Henry

Active Member
How do you maintain an O2 supersaturated H20 solution at atmospheric pressure and average room temperatures?
Hat Freak - I apply a little gas chemistry with Henrys Law and it happens, nothing to it, Google Henrys Law, read it, then you will know how to do it too if you want to.
 

redi jedi

Well-Known Member
Hat Freak - I apply a little gas chemistry with Henrys Law and it happens, nothing to it, Google Henrys Law, read it, then you will know how to do it too if you want to.
I think you need to read Henrys law yourself...considering you didnt even read the info you posted.

Or maybe you don't know that RDWC is not a pressurized system?
 

dstroy

Well-Known Member
But you've got the cathode and anode at the bottom with no membrane barrier so it's not JUST 100% oxygen and hydrogen, it's also ozone and whatever other gaseous byproducts of electrolysis are created when you run electricity through nutrient salts. Ozone is good, since it's more soluble in water than pure o2.

Hat Freak - I apply a little gas chemistry with Henrys Law and it happens, nothing to it, Google Henrys Law, read it, then you will know how to do it too if you want to.
Henry's law states that you cannot increase saturation level above 100% at atmospheric pressure (not even taking temperature into consideration). If you're measuring dissolved o2 in the water right above your overpriced equipment then you're doing it wrong.

I can get the electrodes you are selling from china, and they're much larger and way cheaper for what you get. How you think you can get away peddling a switch-mode dc power supply and the cathode anode assembly in molded plastic for as much as you are is beyond me.

I guess it might be convenient for some people?
 

jeffhan

New Member
Pure bullshit.
Just make sure not even a single light beam goes through the pot in your bubbler, specially through the net pot.
Wrap your bubbler and lid with a foil/bubble insulation, even if it's black.
Spray a bit of Trichoderma over your roots twice a week, if you can add some Mycorrhizae and Azospirillum it'd be a great add-on for your plants.
NEVER EVER USE H2O2 IN YOUR WATER CONTAINER.

Never had a chiller, frequently hit 80ºF, never had any fungus...

And that's it; try it out before coming back with some BS internet stories.
 
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