Gnats! Gnats! Gnats! Please help ASAP

Hi growers. I have a gnat infestation and I have fly traps up, apple cider and dishwasher. I even nuked the soil with hydrogen peroxide and they just coming back… I had a bad batch of soil. And I just can’t get it under control. What can I do because I need to enter flowering asap but these buggers keep coming back for another round.

Any input will be greatly appreciated. I need them gone asap!!!

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run them as dry as possible until they are gone… this will normally make them vanish pretty quickly… they dont hang around long without wet soil… they are such a pain and hatch in phases so it can take some time…had another topic a few days ago discussing this and i think the folks i am helping had the same thing happen and they may have came in their soil… just avoid watering as much as you can… they will eventually leave… you can try mulching with something like sand or small rocks but that doesnt always work… neem oil works pretty good in veg but everything will smell like neem … best thing is run the pots as dry as possible…

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How about pictures? It may not be fungus gnats. Overall shot of the plant and one of the insect for ID purposes.

Can’t really help without more information.

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good point… it could he shoreflies or many other types of pests that can plauge growers…

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How bad is this?

I had some flyin thingamabobs and I just wasnt sure what to do. I used this once and it worked.

It says OMRI listed, but now I feel like I used something scary during my veg phase. Something I need an official disclaimer for.

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have never heard of that… only ever used neem oil or alcohol / water mixes … your prob ok if in veg as long as the ingredients are all organic natural oils and such…

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I was hoping that the people at OMRI had done their homework before allowing this product to be listed. I never got out the ol sherlock magnifier to read the fine print other than the instructions.

It was something I found for products with neem oil and natural insecticidal soap when I was googling around.

I’ll read the ingredients later. Thanks

For $7.50, though, I hope its good.

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honestly your prob ok with it if in veg… ive seem people use all kinds of crazy stuff and the plants be ok… i wouldnt sweat it too much…

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Dont know how to link but Google Fruit fly Bar Pro… seems to work in the house, should be in a tent too??

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For fungus gnats use BTi. It’s the best option.

Get it on eBay. Or use a diluted version like mosquito bits.

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But if I went into flowering would the gnats cause problems? Cos I need to flower soon… Going to be running out of space.

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the issue with fungus gnats in particular is there larve eat the roots and rootlets of the plant starving it of nutrients … the adult gnats themselves are a pain but the larve in the soil damage the roots … i do recall reading somewhere that mosquito dunks will kill there larve… the bio in the dunks feed on their larve…

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When i had gnats I was using fabric pots I would just dunk the bottom half in water and let it soak for a few minutes always made sure the top few inches were dry also had this stuff called gnatgo or gognats something along those lines and was able to clear my problem up within a week or two. You have to be persistent ita never just a one and done kind of thing

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There is only one answer and it’s BTI which you can buy pure (I think) or you can buy it in mosquito dunks at Lowes (or at least the one by me). They are little donut things, rip some off, soak it in your water then water your plants. Do this for every watering for a few weeks. There’s also mosquito BITS made by the same company that you can either soak in the water or top dress with.

Oh, and you’re not using air-pots are you?

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Has anyone ever tried Scanmask?

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I was recommended the Scan mask and it eliminated the worst fungas gnat problem you could ever have

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Haven’t tried it yet does it work?

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It works unbelievably. I got the 50 million so I could use in the yard also. I did 2 treatments but noticed right away after the first a major elimination in the gnats.

Being in the horticulture industry for years we probably have at least 100 potted plants in the house. WE HAVE GNATS! But since the scan Mask we are 99% gnat free.

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Have not used mine yet keeping them in fridge. Running into bigger problems with switching MH bulb to HPS bulb. Plants don’t seem to like the heat or something

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Heat should not be too much different between the 2. How close are they? Maybe raise it a bit?

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