I only use it to clean my pipes/res and for gnats (fungus gnats)...
to clean I mix it down to 3% and spray everything that might be dirty... for gnats I mix it down 4 to 1 from 3% with ro water(44 to 1 from the 33% h202) and spray to water in to about the top inch of coco.
Hey be careful with the 35% stuff guys, it will bleach the shit out of you! While h2o2 is produced in the body naturally as a by product of reactions, higher percentages (like 35%) can not only burn the shit outta plants, it can burn YOU.
its another amazing product, with many health benifits and uses. But it's not a 'more is better' item for sure, do your homework.
There is always a flip side to every coin. Often times someone reads or hears that adding something like H202 CAN help oxygenate ones roots systems..TRUE. But the negatives far outweigh the positives.
H202 Kills EVERYTHING and way too many people only hear the positive side and not the negative affects.
No less than 3 growers I have spoken to this year have been shooting themselves in the foot over this very issue because they really don't understand the products they are using.
This was the scenario all three times (give or take)
Grower reads that roots need 02 and that H202 is a great source.
Grower already has a potent line-up of Beneficial Bacteria (like Great White, Tarantula or Piranha) that are very beneficial and expensive and effective.
Grower has been using those Myco's for awhile and is looking to further better their garden.
I literally watched grower put $100 worth of Bene's in a barrel, and just before he watered he decided to add h202 and unbeknownst to him just killed everything he had just added with 25 cents worth of H202.
I would NOT use H202 unless you are a hydro grower that knows exactly what you're putting in your mix. I would not even use it on the surface (of soil) for gnat control as it is more likely to cause more harm than good.
I agree with Bornon completely, it CAN BE and amazing product, but I would venture to say that Growers who don't know cause much more harm then benefit with it.
It's important to know the exact detriments as well as the benefits of anything you add to your mix. Don't add something cause you read it somewhere. Chances are they only told you the good and not the bad.
id use 3% if your going to use it at all; 35% is something youd use on yourself VERY CAREFULLY!
it is a great way to oxygenate the roots but like d said it will kill anything and everything off; so unless your dealing with some serious root rot/fungus problems, Pathogens or insects id stay away from it in general
If you are in soil/soilless; add some form of aggregate to your mix, aerate your water, use a enzyme product, etc. H202 of that % does wonders for cleaning tools, surfaces, etc. If you are in hydro and running a dead rez, H202 can help with algae, and other forms of build-up.
Imo, it is better suited for a cleaner in the garden, rather than a additive.
In a hydroponic environment you usually want everything to be sterile. Hydrogen peroxide works wonders for this, particularly in deep water culture. Besides keeping everything sterile, it adds extra oxygen to your solution. It is also good for cleaning out your system between reservoir change outs.
You can go as high as 5 ml per gallon per day with no harmful effects. Standard is 3 ml per gallon per day. One guy I know gives them 7 ml every three days and has for years.
3 ml = 1 tbsp per 5 gallons
1 tsp = approx 5 ml
1 tbsp = approx 15 ml
I always used the little measuring shot glasses that they sell at hydro stores
If you have problems with root rot you would want to go with the 5 ml number. Young plants can't handle as much, I would go with 1 ml per gallon until they develop solid root systems.
Hydrogen peroxide will kill off everything in your reservoir, which is usually desirable in hydroponics. But of course this means you cannot use it with organics.
I have used it in potting soil with good results. It works particularily well if you have drainage problems. I had a crop once that just didn't drain for shit. It was taking 5 - 6 days between waterings to dry out. I started giving them 1 tsp per gallon 35% H2O2 and they dried out in 24 hours. I had to water them 7 times a week. The effect is that dramatic.
It's up to you to decide whether you want to use this or not, but if sterile is your goal then this stuff is very safe and effective when used correctly. If you get it on your skin just rinse it off. If you accidentally get some on yourself, you will know in about five minutes lol.