How much h202 to kill fungus gnat larvae?

nicksol86

nicksol86

Well-Known Member
I'm in deep water culture hydroponics, NOT soil! How much 3 percent hydrogen peroxide, with how much water do I dilute to kill fungus gnat larvae? I read online 1 part hydrogen peroxide per I think it was 3 or 4 parts water. I tried that on my northern lights in my hydroton and it literally fried her and killed her. Don't want to do the same thing to my pineapple express. Help please
 
Airwalker16

Airwalker16

Well-Known Member
nicksol86 said:
I'm in deep water culture hydroponics, NOT soil! How much 3 percent hydrogen peroxide, with how much water do I dilute to kill fungus gnat larvae? I read online 1 part hydrogen peroxide per I think it was 3 or 4 parts water. I tried that on my northern lights in my hydroton and it literally fried her and killed her. Don't want to do the same thing to my pineapple express. Help please
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I'm not too sure, bit maybe it'd be better to use 29-32% h202 so you could use less liquid to have to add to your nuts mix?
 
nicksol86

nicksol86

Well-Known Member
But it doesn't say for fungus gnats. I don't know. The 3 percent grade you buy at any store or pharmacy for cuts has bad shit in it that you might not want to feed your plants. That's why food grade is preferred and 34 or 35 percent is preferred but diluted down so it's safer to use. You can also use distilled water to mix up a peroxide batch down to 3 percent.
 
nicksol86

nicksol86

Well-Known Member
nxsov180db said:
The max h202 of 35% is 10ml/gallon, I know this from actual experience not hear-say. More than that amount you'll start to see fan leaves crinkle up and die.
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10 ml per gallon of 35 percent? What? That's way too much. Nice try though
 
simpleleaf

simpleleaf

Well-Known Member
My quick and dirty formula for H202 is: 35% x 3% = 1.05% (basically a memory aid)

That means if I add 3% of 35% H202 to some water, I end up with something close to 1% H202. It's easier to calculate and weigh that way than doing a true percentage, although there's a small error.

1000 g (of water) x 3% (of 35% H202) = 30 g of 35% H202 ≈ a liter (+ 30 g) of 1.05% peroxide.
 
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nicksol86

nicksol86

Well-Known Member
simpleleaf said:
My quick and dirty formula for H202 is: 35% x 3% = 1.05% (basically a memory aid)

That means if I add 3% of 35% H202 to some water, I end up with something close to 1% H202. It's easier to calculate and weigh that way than doing a true percentage, although there's a small error.

1000 g (of water) x 3% (of 35% H202) = 30 g of 35% H202 ≈ a liter (+ 30 g) of 1.05% peroxide.
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You lost me bro
 
Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
i used 3% till i found a source of 30%. you can regularly use 10ml per gallon of 3% with no ill effects, and it will keep your rootzone clean. you can go up to 20 ml per gallon for shock treatment, but you don't want to run it above 10 constantly, or it will start to dissolve healthy plant material.
now that i've gone to 30%, i've found that 3 ml per gallon is ok for constant use, you can go up to 5 or 6 for shock treatment, but don't run it that strong for more than one day.
i actually only use it every third or fourth feeding, at 3 ml per gallon, just to keep things from getting started, and i don't hardly ever see gnats, and haven't had any root rot type problems since i started using it
 
TIMtoKILL

TIMtoKILL

Active Member
I had some problems with roots a month ago or so. In my 25 gallon system I threw in ~1.5 cups of 30%(whatever they sell at the store). Put it through the net pot. I then put in Half of that every other day. Keeps it clean and keeps the roots happy.
 
Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
TIMtoKILL said:
I had some problems with roots a month ago or so. In my 25 gallon system I threw in ~1.5 cups of 30%(whatever they sell at the store). Put it through the net pot. I then put in Half of that every other day. Keeps it clean and keeps the roots happy.
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they sell 3% at the store, a cup and a half of 30% and you'd have a res full of dissolved plants.
3% doesn't hurt you or bleach your skin bone white. gets some 30 % on yourself and you'll realize it pretty damn quick, and where ever you got it looks like you got whiteout on yourself
 
nicksol86

nicksol86

Well-Known Member
Roger A. Shrubber said:
i used 3% till i found a source of 30%. you can regularly use 10ml per gallon of 3% with no ill effects, and it will keep your rootzone clean. you can go up to 20 ml per gallon for shock treatment, but you don't want to run it above 10 constantly, or it will start to dissolve healthy plant material.
now that i've gone to 30%, i've found that 3 ml per gallon is ok for constant use, you can go up to 5 or 6 for shock treatment, but don't run it that strong for more than one day.
i actually only use it every third or fourth feeding, at 3 ml per gallon, just to keep things from getting started, and i don't hardly ever see gnats, and haven't had any root rot type problems since i started using it
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2 to 3 ml per gallon sounds more realistic then 11ml per gallon like someone stated above us
 
Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
nxsov180db said:
I actually don't think you're going to be able to use enough peroxide to kill fungus gnat larvae. If an oxidizer doesn't kill a plant it's not going to kill an animal. You need to look into something like Bonticare ES.
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it will kill them, just takes 2 or 3 treatments to get ahead of the game. it's like mites, they lay eggs, so you have to come back a few times to get them all. plant roots are tougher than gnat maggots, by a good ways.
the best way to get rid of gnats is to let your soil surface dry out well between waterings. this dries out the eggs and breaks their life cycle. if they're already established, h2o2 will kill them, and weekly applications will control a re-occurence...but really, let them dry out good before you water again....the only exception is coco, and then i recommend h202 and gnat nix together, because they'll always be in coco
 
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nicksol86

nicksol86

Well-Known Member
Roger A. Shrubber said:
it will kill them, just takes 2 or 3 treatments to get ahead of the game. it's like mites, they lay eggs, so you have to come back a few times to get them all. plant roots are tougher than gnat maggots, by a good ways.
the best way to get rid of gnats is to let your soil surface dry out well between waterings. this dries out the eggs and breaks their life cycle. if they're already established, h2o2 will kill them, and weekly applications will control a re-occurence...but really, let them dry out good before you water again....the only exception is coco, and then i recommend h202 and gnat nix together, because they'll always be in coco
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My buddy never had them in coco he said but he used to get them in soil and hydro. I guess it can be different for everyone.
 
nicksol86

nicksol86

Well-Known Member
nxsov180db said:
3ml is good for maintenance. But maintenance isn't what you're after right now..
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Well like I said I did 4 parts water and 3 percent h202 at 1 part only and it killed my young Northern lights. Was perfectly healthy til I did that and then it literally fried it and droopy and didn't want to recover. Had to chop it and call it a loss. I'm not doing that again.
 
Roger A. Shrubber

Roger A. Shrubber

Well-Known Member
does that solution sit for a while before you use it? 10ml per gallon of 30-35% h2o2 WILL dissolve roots and stems, i've watched it happen.
either that sits for a day or more before it gets used, or you got fucked and that's not 35% h2o2.
 
Johnny Lawrence

Johnny Lawrence

Well-Known Member
I have not dealt with fungus gnats since getting Lock Down pads. They're a bit overpriced for what they are, but you could easily DIY some if you're broke. Oh, and they're useless(or a huge pain in the ass) if you have any type of top feed system. I run ebb & flow.
 
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