Dissolved oxygen in RDWC, is high DO very important in your opinion

[JohnM]

I found this piece last week. It's a little over 8 years old.
12/6/2007 Dissolved Oxygen, oh my - https://www.icmag.com/ic/showthread.php?t=75568
“At the ideal temperature of 20-22 celcius (68-71.6 fahrenheit) the water can only hold about 9 ppm dissolved oxygen. We can temporarily raise the dissolved oxygen levels by chemical reaction, such as adding H2O2 or more permanently raise it by causing waves at the surface with air pressure...
Biochemical oxygen demand for the cannabis plant is only ab every strain of cannabis I have grown in the past 6 years only requires 7 ppm total dissolved oxygen. I gave up on looking for differences in 7 vs 14 ppm dissolved oxygen in DWC containers after seeing six different strains of four plant test samples per strain perform essentially the same. One thing that more dissolved oxygen does help with though, is keeping silly organisms like pythium in check.”

Question: do you really think you can increase the DO to 14 ppm DO with water temp @ 20-22C (68-71.6F), by simply “causing waves” especially when water at that temp can only hold 9 ppm DO max? I can see where you can increase the dissolved nitrogen saturation with air (aeration) , but 9 ppm DO is all there is using air (aeration). At least that what the DO Saturation chart says. And many growers are limited by the DO Chart, its the real deal.
Growers never have low O2 problems until they see root rot. When you see root rot you have a low DO problem. Root rot doesn't grow when the DO is high.
Question: H2O2 is a popular anti-ceptic and potent oxidizer, but Have any of you ever used “O-Tabs” to increase your nutrient DO? http://www.amazon.com/gp/product/B0007RP7HW/ref=pd_lpo_sbs_dp_ss_2?pf_rd_p=1944687762&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B004RC5C8W&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=08J4WYTN6FSQAQM5ZZNM
John

 

[LostTribe]

I doubt have never heard of o-tabs and would not use them.....I run full on hydroton ebb drip buckets and don't bubble my rez at all and get great stuff every time....

 

[sdd420]

I grow in a flood and drain system. The tray sits on the reservoir...you get a waterfall affect as it continuously drains and gets super oxygenated effect. I've left it running by accident and no problem for over 24 hours. Temps were 60-75 in reservoir plants love it in hydro

 

[JohnM]

I grow in a flood and drain system. The tray sits on the reservoir...you get a waterfall affect as it continuously drains and gets super oxygenated effect. I've left it running by accident and no problem for over 24 hours. Temps were 60-75 in reservoir plants love it in hydro

In you opinion, what DO saturation do you achieve what you are call "super oxygenated?"

 

[tontaube]

Sorry, I translate with Google translator.
The salt content of the nutrient solution has an influence on the amount of dissolved oxygen, most of the data on maximum O2 saturation refer to clear water.
You can easily decide for yourself, you only need an O2 meter and a plant in a very small DWC.
This work is from the year 1945 in German language, simply copy & paste in Google translator http://www.ngzh.ch/archiv/1945_90/90_2/90_17.pdf

Oxygen diffusion as a limiting factor of
Breathing plant roots
From
H. WANNER (Zurich)
(From the Institute of General Botany, University of Zurich)
(With 10 illustrations in the text)
introduction
The efficacy of the cellulitis is based on its preservation on one
Approximately constant level. This is achieved by the fact that they can be used within
Further limits independent of the oxygen concentration (WARBURG
And KUBOwiTZ 1929), as well as the substrate concentration (WARBURG
1934). The independence from the concentration concentration is conditional
By the very rapid reoxidation of the respiratory ferment (cytochrome oxidase),
Whereby this is almost always completely in the autoxidisable form of iron
is present. The activation of further redoxases between respiratory ferment
And substrate (cytochromes, etc.) allows practical independence
From the concentration concentration.
Year 90 H. WANNER. Oxygen diffusion. 99
The circumstances under which WARBURG and KUBOWITZ (l, c.) Independence
From the oxygen concentration to the astonishing
Low oxygen partial pressures of 10-5 atm. As, thanwie,
But in most cases not too. These researchers were found in yeast cells
A higher critical oxygen voltage than that of the main one
Used Micrococcus; They led this increase to an inadequate
Oxygen supply of the cell retina; Such a must be natural
The larger the cells are. Outside the cells
In the Barcroft-Warburgschen used in these experiments
Method no diffusion difficulties occur, since the respiratory gases
Are evenly distributed in the medium by the shaking of the vessels.
When investigating the breathing of whole tissues must address the problem
The sufficient supply of oxygen to all the cells of the tissue
Greater attention is given to the case of isolated cells. These
Claim warbed WARBURG (1923), the maximum thickness of tissue sections,
Which are to be used for respiratory measurements.
For this purpose he used the measurements of the diffusion coefficient of oxygen
In muscle tissue of KROGH (1919). The so-called "boundary section thicknesses"
Have been used in all studies on the breathing of animals
Tissues.
In plant tissues similar problems occur, but they have
Have not yet received the due attention. The in this
Work to be described and deliberated went from the
Already observed, that the breathing of plant
Roots of relatively high oxygen concentrations
drop. The question therefore arises as to which factors are required in
In this case the level of the critical oxygen concentration, or which
Are the limiting factors under the given experimental conditions
Of the root respiration. It quickly became apparent that the substrate concentration
As such does not come into question; The investigation remained
Of the diffusion ratios of oxygen in the area surrounding the root
Medium, as well as in the root itself
Experiments were significantly facilitated by the use of a polarographic
Method of oxygen determination.
The execution of this work was made possible by a scholarship from the Foundation
For biologically-medical scholarships, for which the author has his most binding
Thanks. Thank you very much
Is the Prof. Dr. A. ERNST for his always expressed interest in the execution
This work, for the procurement of a Multiflex galvanometer and the transfer
Other resources of the Institute. I am indebted to my brother, Mr. W. WANNER
Help with the treatment of mathematical-physical questions.
Test method and methodology
As a test material, roots of wheat germ seedlings (Triticum sativum)
And of Allium Cepa onions. The wheat seedlings were grown in the dark at 18 ° C
(Thermostat) in a nutrient solution according to ToTTINGHAM of the following composition:
100 quarterly inscription of Naturf. Company in Zurich 1945
Fig. 1
Circuit diagram of the used
Amperometric apparatus.
A = accumulator (2V); Ne _
Normal element; K = capillary electrometer;
U = changeover switch;
G = galvanometer; R = Respirometer vessel.
a +
: H20 1000 cc, KNO3 0.06 g, Ca (NO3) 2 0.24 g, KH2PO4 0.18 g, MgSO4 0.12 g, FeCl2
Track. The onions were drifted over the tap water at the same temperature
Of roots.
For the investigation, we used roots from the permanent zone; The Würzzelspitze
And the stretching zone was measured in a length of 15 mm (from the root tip
Measured). This procedure is for the sake of clarity
Presence of a gradient of respiratory intensity in the longitudinal direction of the
Root necessary. This gradient is in particular in the rootsp

 

[Douglas.Curtis]

You'll find fewer issues with higher DO levels. As mentioned, chemical means are to be avoided.