H202 Concentrations for Optimal Root Growth

[cashmunny]

Came across an interesting article.

https://www.growertalks.com/Article/?articleid=22058

They were able to exceed the solubility of oxygen in water by generating the oxygen with ozone in situ. At room temperature the solubility of oxygen is 9 ppm. Supersaturated solutions are possible but presumably they had to constantly generate oxygen to maintain concentrations > 9ppm.

The bottom line is that 30 ppm dissolved oxygen seems ideal. Achieving this with hydrogen peroxide seems doubtful. Since it takes 2 molecules of peroxide to dissociate into one molecule of oxygen I've adjusted the table below to account for that.



Desired O2 PPM 5 10 15 20 25 30

3% H202 mL/L 3.33 6.67 10.00 13.33 16.67 20.00
35% H202 mL/L 0.29 0.57 0.86 1.14 1.43 1.71

3% H202 tsp/gal 2.56 5.12 7.68 10.24 12.80 15.36
35% H202 tsp/gal 0.22 0.44 0.66 0.88 1.10 1.32

 

[hayday]

So is 15.36 teaspoons of 3% in a gallon of water-nute solution ok and safe for plants? That would be 30% at mixing.
Ok for hydro and soil?
I skimmed thru the article and it said h202 was unstable and did not stick around long but will it effect my plants adversely?

 

[Chris P Bacon]

I was recently reading this article (pdf) https://www.dramm.com/media/Dissolved%20Oxygen%20in%20the%20Greenhouse.pdf

It states, despite anecdotal evidence in forums that H2O2 boosts growth, that "When put into water, H2O2 converts to H2O and O2-. O2- is the free radical form and indiscriminately oxidizes everything, including healthy plant cells – we don’t want this one. O2 is the diatomic form of oxygen and is readily absorbed by a plant’s roots – this one we want. H2O2 is best left as the cleaning and disinfection tool it is traditionally known for in horticulture."

From what I have read, for what it is worth, H2O2 can also effect pH stability in reservoirs but this was anecdotal.

The article suggests that ozone is a better method.

I have just bought an ozone generator and have rigged hoses with air stones to be able blast the rezs in my tents for an hour a day, depending on results. The generator can be used to disinfect the grow room between grows and and for other tasks around the house like cleaning fruit and vegetables, purifying water or getting rid of unwanted smells.

 

[Speed of green]

Would ph stability become an issue at higher dissolved oxygen levels?

 

[troutman]

It may be good idea to water less to increase oxygen in a grow medium than use hydrogen peroxide.

 

[Chris P Bacon]

Would ph stability become an issue at higher dissolved oxygen levels?

I don't think so, at least not as much as with dissolved CO2 rates increasing, which is one of the issues using air pump and stones where one is pumping CO2 into the rez.

https://www.fondriest.com/environmental-measurements/parameters/water-quality/ph/

"The above equations also explain why rain has a pH of approximately 5.65 ¹⁵. As raindrops fall through the air, they interact with carbon dioxide molecules in the atmosphere. This creates H2CO3 in the raindrops, lowering the rain’s pH value ¹⁷. A pH level of 5.65, though acidic, is not considered acid rain. Natural, unpolluted rain or snow is expected to have pH levels near 5.6, assuming a standard atmospheric CO2 concentration of 0.0355% ¹⁵. Acid rain requires a pH below 5.0"