Guide to Hydrogen Peroxide in hydroponics systems.

I found this pretty easily using Google, but I thought I would share the info. If it has been done already I apologize.

This is originally from http://www.jasons-indoor-guide-to-organic-and-hydroponics-gardening.com/using-hydrogen-peroxide.html

There are no doubts about the benefits of using hydrogen peroxide properly in a hydroponics system. This becomes especially true if your nutrient reservoir is kept above 72 degrees. Warm water holds less dissolved oxygen, and therefore encourages the growth of more viruses, fungi, and anaerobic bacteria. Using hydrogen peroxide adds oxygen to you water and cleans the water of pathogens. Benefits include healthier root systems, increased nutrient uptake, thicker stems, and bigger leaves.

One expert claims it should be used on all soil gardens as well as in hydroponics sytems. Knowing as much as I do about beneficial fungus and micro-organisms and the benefits they provide to living plants, I am shy in taking this advice. However, when this first line of defense fails and plants become sick I often resort to using hydrogen peroxide treatments on my soil grown plants.


The chemical formula for hydrogen peroxide is H2O2. You may notice it is simply water with an extra oxygen atom. In fact, as hydrogen peroxide breaks down in a solution the result is oxygen and water. Its application helps deliver oxygen to over watered plant roots and helps to sterilize the growing media by killing harmful anaerobic (not oxygen compatible) bacteria and pathogens that cause disease. This includes bacterial wilt, pythium fungi, fusarium fungi, and others.

Using 3% Hydrogen Peroxide
In your Hydroponics Garden

I avoid using hydrogen peroxide you commonly find at drug stores. This is because such low percentage (3%) solutions are unstable, and chemicals are added to the peroxide to keep it from breaking down before it can be used. I did a little research because I did not know what chemicals were used for this, or if the plants uptake these chemicals, or if there was a health risk associated with any of these stabilizing chemicals.

Hydrogen peroxide is usually stabilized with acetanilide. Acetanilide is a synthetic compound that was first used for its fever reduction and pain killing properties in the late Nineteenth Century. For many years it was utilized as an alternative to aspirin to treat various ailments, but large scale medical use stopped when the toxic side effects of consuming acetanilide became apparent. This was enough to convince me to use 35% hydrogen peroxide instead.



Using 35% Hydrogen Peroxide
In your Hydroponics Garden

Firstly, 35% peroxide is caustic and should be treated with the same caution as a strong acid. 35% strength hydrogen peroxide should be readily available at any quality hydroponics supply shop. The stronger concentrations do not use the added stabilizers.

The recommended dosage is to add 2-3 ml to each gallon of water, however, I use 5 ml per gallon and have never had any problems. At every nutrient change treat your fresh water using hydrogen peroxide. The general idea is to let the hydroponics system circulate the hydrogen peroxide solution for about a half hour to let the peroxide work against pathogens and to let the solution stabilize before adding your nutrients.


The beneficial effects of using hydrogen peroxide last about 4 days. There are some gardeners who add a little peroxide to their nutrient reservoirs every 5 days in between nutrient changes. If you decide to do this, stick to the guidelines and always make sure your solution is thoroughly mixed before exposing your plants roots to it. Another option is to top off your nutrient reservoir with peroxide treated water whenever it is low.

Word. Im thinking of switching from Hygrozyme to H202. It says 35% in that post, but ive heard people say the 50% grade is more effecient, Anybody know?

It would require you to use less but I just heard it can be used to make bombs. So they will take down your info which is a little shady. I might just go for 12% or something and use more of it.

35% food grade works great, but a tad expensive @ $15 a quart... no name recording. Check your local health food store.

I'm moving away from h2o2 and attempting to replace it with hygrozyme. I like beneficial bacteria and if your using ANY organic nutrients you should not be using h2o2. Now if your doing pure chem ferts, and going for a sterilized system, h2o2 is the way to go.

I use 29% H202 and have been adding about 4 tablespoons for 20 gallons every 3 days. Its $10 per liter from grow store.

Why no H2O2 with organics? I heard hygrozyme builds up the bacterias immunity and eventually your using more and more of it to control bacteria. H2O2 doesn't build up superbacteria.

Someguy15 said:

35% food grade works great, but a tad expensive @ $15 a quart... no name recording. Check your local health food store.

I'm moving away from h2o2 and attempting to replace it with hygrozyme. I like beneficial bacteria and if your using ANY organic nutrients you should not be using h2o2. Now if your doing pure chem ferts, and going for a sterilized system, h2o2 is the way to go.

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See for me hygrozyme works well, the thing is though my roots are still slightly brown and i feel like they could be in better shape if i used h202 instead. Im Using General Hydroponics lucus formula so i think i would be fine with h202.

Hydroneer said:

Why no H2O2 with organics? I heard hygrozyme builds up the bacterias immunity and eventually your using more and more of it to control bacteria. H2O2 doesn't build up superbacteria.

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Ya know this could be true, Cause originally my roots were pretty clean, slowly they have got kinda brown, not slimy at all, but just kinda fucked up. Ive constantly been using the same amount, maybe this is the reason its slowly gotten worse.

Yeah, maybe what you could do is alternate. Use H2O2 to clean out the system every few cycles and start fresh. I also heard of people using bleach to basically chlorinate and do something similar to H2O2 but personally I would be terrified to bleach my plants!

Hydroneer said:

Yeah, maybe what you could do is alternate. Use H2O2 to clean out the system every few cycles and start fresh. I also heard of people using bleach to basically chlorinate and do something similar to H2O2 but personally I would be terrified to bleach my plants!

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Ya that sounds like it would be a good idea! Ive heard people say that on this site to, but im right with ya that just sounds like a bad idea.

I used 35% h2o2 in some plants that had major soil rot and compaction issues. I think I mixed it up at about 10Tbs per gallon at 3%. Yup, strong as hell. It actually fizzled in the soil. I saw no bad things happen from my plants, and my little gnat problem is nearly gone. The soil LOOKS like its aerated a tad too. Who knows, but from what I've read, its bad in organics bcuz it kills the good bacteria. However, Im using earth juice, and I figured what the hell, its time for a flush anyhow, and went gung ho. I may do one last h202 flush before I let my babies dry for end week. I am going to be using it in my hydrosetup for sure. Probably add a little bit to the weekly flush. I have also started using about 1T per gallon of 3% in tap water to help kill the bacteria, while I wait for the chlorine to dissapate. Then after the h202 is nearly gone, I add my EJ and begin the 48hr stone aerate. They seem to luv it so far. Maybe its all for nothing, but i Like the idea of a little excess oxygen in the water for cleanup. Of course. read up...opinions vary and I'm not a chemist or botanist.

Sounds legit. You did mix it pretty strong but if thats a flush thats fine. I'll use weaker concentrations for daily watering and replenish it every few days. I had red algae last flush, and this time I smell the same mold I smelled on my clothes in my closet so it seems I keep getting different contaminants lol. Ill be getting the H2O2 pretty soon.

Alright folks, I just got my 35% H2O2 and did about 2-3 ml per gallon of water like recommended by the guide I found (and it seems to be the only 35% guide around).... The plants started wilting within an hour, so I flushed them with lots of fresh water... I am starting to think he meant DILUTE the H2O2 to 3% then use 2-3ml per gallon. I hope you guys don't have the same results I did. If I just killed my babies I will be very sad =(

Ok the plants are perked up again, I think its safe. I only let the H2O2 sit for about 15 minutes before watering so perhaps it was too caustic and the oxygen had not been released yet. I will refill my reservoir and try again with much less H2O2 and let it sit for 30 as suggested.

[how much should i use for soil application...im having drainage problems with my soil, and having trouble keeping the plants from being overwatered....

Ummm.. overwatered= Wait longer and they weigh less before watering.

I have been using about 1 tablespoon of 3% peroxide in my tap water as I wait 3-4 days for chlorine to dissapate. I bought 35% and diluted it, so dont quote me on exacts. When I blasted my soil with about 1Tbs of 35% per gallon, it fizzled the soil, killed some gnats, and as it fizzled it actually seemed to aerate the soil. However, my plants were nearing harvest and VERY mature.

Hydroneer may be having issues in hydro use, but for soil, I think
1TBS or less per gallon of 3% every other water (not when using nutes), serves a viable purpose.

anyone else have opinions or proof?

I just started using 3% about a month ago in my DWC set-up. Noticed a huge difference in root development. They stayed nice and white and always smelled really fresh. With all the talk about nutes and lights, H2O2 definitely deserves more consideration from people. My only recommendation for Hydro is to not mix organic with it. I'm not a chemist or botanist either, but the 3% works just fine for my 6 gallon res. I add 10 ml per gallon when I mix my nutes, and whenever I top off. A liter of the stuff at Wal-mart is only $1, well worth the investment.

Chlorine is cheaper and safer and it is easily tested with a simple Hach Colorimeter you can buy on ebay for about $25 to $50. The testing reagent costs about $20 for 100 tests. For treatment you dose to 2 ppm and maintain 2 ppm for 7 days, then maintain at 0.5 ppm for preventative measures after that. It only takes testing for a 5 or 6 days to find out how quickly your system out gases the chlorine. 4.5 ppm is the EPA allowable level for tap water. Don't hear stories of tap water killing plants do you. There are many thousands of people growing mj with tap water with 2 to 4.5 ppm of chlorine and they do not age it or neutralize the chlorine. Both H2O2 and chlorine are oxidizers, however H2O2 is a stronger oxidizer so more dangerous. H2O2 offfers no residual disinfection. Its disinfection qualities are immediatte. The H2O2 not immediattely uses as an oxidizer immediattely turns to DO and it does no further sisinfecting after that point. Chlorine depending on te, mperature and the amount of aeration continues tp provide residual chlorine for dissinfection until it is outgassed. About 24 hours. The safe way to use chlorine is to add it to the 2 ppm level, let it drop to 0.5 ppm and dose back to 1.0 ppm and dose everytime it drops below 0.5 ppm. Most commercial greenhouses use chlorine at levels of about 4.5 ppm injected into there actually hydroponic feed lines just before their spray heads.

No oxidizers should be used with organic fertilizers. With organics your stuck with hygrozyme and other chicken manure based enzyme solutions. Yes Hygrozyme is simply the leachatte from composted chicken manure.

So fatman. Can i learn from you that perhaps using tap water immediately after adding nutes, ph issues aside, will be a benefit since the chlorine will act as h202 would, only more stable? I have been using tap water only, and usually when i flush w/o letting the chlorine dissapate, i dont notice it killing my babies. Of course, i use organics in soil, so Im not able to just use h202 or chlorine in my soil grows. Thanks for the info.

Perhaps using the h202 during hydro nute change, for a quick clean, then relying on the chlorine in the tap water to help for the first few days of a new nute tank? Personally on my first hydro grow, im only going to use the h202 before i let the water sit for 48hrs. Then perhaps I'll use some during a clean water flush. Im using AN, so im skeptical about deviating from their recipe for my first hydro. Hopefully keeping a clean tank(s) will head off the problem of mold and bacteria before it starts.

Anyone else have any info on the hydroponic use of h202?