Problem with fungi gnats

Discussion in 'Growing Marijuana Indoors' started by Johnb142, Aug 24, 2017.

  1. Single indoor plant just 1 week into flowering and just 2 days ago i noticed these flies i tried using methods with things i have at home first i put out a tray with apple cider vinegar and a drop of dish soap to trap the adult ones and i uses the hydrogen peroxide and water mixture for the larvae yesterday morning i checked on it before i went to bed and there was nothing but a few adult ones which i killed and this morning i check and im back to where i was before they're all over anyone have any recommendations to what i should do? Any specific things i can pick up at the store that will help?
  2. I had the same problem few months ago and there pesky little fuckers,I did same thing with peroxide it help and keeping caps on water jugs ,no spills and maintain good temps high 70 s and low humidity will help a ton.You may wanna do the whole peroxide thing again to be on the safe side..
  3. Yeah definitely it looked like it worked fine until this morning i was just looking for something stronger than hydrogen peroxide but in your case did it take more than 1 watering with the hydrogen peroxide or did it work immediately for you?
  4. It worked ,I did it 3 times,and used these sticky pads,and added an oscillating fan which blows directly at the soil ,After the first use, I let my soil dry out ,put up the pads and then hit it again after it dry s out again,Then waited a 3rd time for my soil to dry good and did the same thing again,the biggest issue was temps and my humidity was hey making it perfect for them to breed,I keep my tent clean like a lab now,lol so far so good.I also may have brought them in initially, by bringing an outdoor plant in which was a dumb move altogether,2nd time I got burned doing that. 1st time was spider mites and there a whole other story.Hopefully this will help u out ,
  5. #5 storz, Aug 24, 2017
    Last edited: Aug 24, 2017

    multi attack approach for soil grows--IT WORKS!!!!!
    1) when filling your pots sprinkle Mosquito Bits into the soil(about 4 cups worth while filling your #5 pot) so that the bits are dispersed throughout the medium
    2) initial soil drench with beneficial nematodes (Knock out gnats is what I use) Rec you use this a few times throughout the grow.
    3) sprinkle liberally Mosquito Bits on top of soil
    4) follow up that with a liberal layer of diatomaceous earth
    5) follow that up with a solid 1 inch of gnat nix on top of everything(I have been told sand works too)
    6) sticky traps hanging around canopy and some at soil level
    +++note++ fill the bottom of your pots with large growstone to prevent breeding at the drain holes of the pots++++++
    Its a lot I know but I have ZERO gnat problem. In fact I look at the sticky traps as a monitoring method to determine how my set up is working. I will see one or two on the trap but they are coming in from outside and not necessarily breeding in my grow area. This system is proven to work!
  6. I get fungus gnats occasionally and 3 drenchings with Gnatrol - BTI takes care of the larvae. Yellow stickies takes care of the adult fliers. I never had any luck with the hydrogen peroxide. Good luck.
  7. What are the risk of me using hydrogen peroxide again before the soil dries out? Theres more of them everytime i check i wanna ger rid of them asap
  8. Hey
    Hey mick quick question do you think itll be bad if i try attacking these gnats before the soil from the last time dries up? Im just worried the more time i take the more damage they can do
  9. I got the whole article that I used and it worked,I ll PM it to u,
  10. What damage have the gnats done?

  11. So far nothing i saw somewhere online that eventually the larvae start eating at the plants roots im just wondering how much time do i have before that happens
  12. For what it's worth, I've been doing this quite a long time and I've never once seen gnats be anything more than a nuisance.
    Take a few basic measures to keep them under control and they'll be just fine - seriously.

    Gnats eat decomposing organic matter so if you grow in soil expect to see them sometimes but they won't hurt your plants like Mites and other pests can.


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  13. They can suck in flower when they get stuck in your buds but that's about all I've noticed they do
  14. I use a small oscillating fan blown towards the soil just under the plants. They don't fly very well in wind, so it keeps them from living and repeating their cycle of life = alot less of them and their numbers decline.
    It's worked for me.. I've also heard an inch of sand will work.
    Fyi...they are already in the soil you buy..
    I'm reusing soil, so maybe I won't have them.
  15. Try adding neem cake mixed directly into your soil or topdress a few heaping tablespoons per container and work it in with your fingertips.

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  16. come on guys. hes over watering or there would not be a problem . if the soil dried up on the top layer before it was watered there would not be bugs. so you do not have enough drainage in the soil . next time get some perlite mixed in . this time just get some sand put it on the top of the soil problem solved .
  17. Thanks man thats a relief this is my first ever grow im already in flowering i was afraid those gnats would be a more serious problem
  18. With sand on top would i still water normally or would i have to water from the bottom?

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