Little black knats

Just saw little black knats when I watered coming up from the 707 soil, I do not see anything when I do a forum search for them, what can I do to/ use to rid my room of them. Ugg

I can’t seem to edit my post or tag anyone, has this process changed?

Cover the top of your soil with diatomaceous earth or gnat nix (recycled glass). Could also spray soil with need oil. If that doesn’t work then Hydrogen peroxide @3%, but this will kill your soil beneficial microbes.


Thank u WA, do they cause damage to the girls

All of those are known solutions regularly used.

Hello @Okie70
If they are fungus gnats then yes their larvae that the adults lay in the top of soil can eat your roots.
I use this anytime I set up new pots in the beginning as a preventative measure or add on top of existing soil if more is needed. This is a safe option as it uses a bacterial critter that eats the larvae but won’t harm your plants nor and living critters in your soil if your using a natural grow it is called BTi i is the important part as that particular strain eats the fungus gnats larvae while others may not.

Hope this helps and HAGD


Helps a lot @Skydiver thank you, I am going after them


Yellow sticky traps also to catch the adults. Also have used white vinigar soap and water in a bowl to catch them


They can kill your plants @Okie70 , thats pretty bad, i always have the below product at hand. This will kill the larvae not slow them down like other products.

Bti Bacillus thuringiensis israelensis

you need to get the above product, you can get it on ebay mix a strong solution then PH the water to your requirements it will kill the larvae worms which eat the roots of your plants, you need to do it every watering until your ontop of them, i dont have any probs now but still use it at least once a month just in case.

Kill Fungus Gnats with 1 oz GNATROL BTI bacillus thuringiensis israelensis

Brand new

From United States

Seller: organicbti (4,768) 99.7%

Buy It Now

Item: 264084569719

sorry not allowed to put the ebay link on but the sellers details are above and they are in the USA
also if you have any other indoor plants treat them also.
Compliment this with yellow sticky boards and topdress with gnatnix which is a recycled glass.


The mosquito bites above has the same BT strain of Bacillus in it.


Yes it does but only 2.86% other ingredients 97.14%, the BTI i get is 100%, plus i dont have to pay for marketing, fillers , and the products name!
Plus the pure is fine to use very safe, check the warnings on the bits package, and the pure is a lot more economical to use :+1:


I have to say though that the one above is American and is around 37% as i could not find the one i purchase that sells in America, as i live in Australia there is a buisness on ebay that sells it, plus its 100% organic.


These guys gave great advice and suggestions. I personally use Gnat Nix or Mosquito Bits because DE gets chalky when watered :v::bear:


The BTi @Hungrybud recommended was the ONLY thing that worked to eradicate my fungus gnats. I tried gnat nix, sticky traps, neem oil, de. BTi took a few weeks, but it killed the gnats and didn’t harm my plants or the soil.
Thanks for that tip👍


No worrys mate

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Seriously, I’d tried everything.
BTi was the answer. You saved my harvest. Thank you :+1::+1::+1::+1:

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The quick fix is to cut up a potatoe and place them on top of the soil. The lava will go to the potatoe which in two or three days throw away and replace with another. Works great believe it or not it really does.

BTI has no dangerous chemicals, doesn’t interact with any mammals, fish or plants and is targeted directly at just a few insects. It is 100% safe to use in a composting worm bin.

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Bti coming, potatos are in place and bits are due to deliver tomorrow, thanks to all for your advice and quick responses

@Killadruid @Hungrybud @MattyBear @garrigan62 @SlowOldGuy @Drinkslinger @WickedAle so now I have seen thru a 100x scope little black dots on the back of some leaves, unable to get a pick thru it with my phone. Leaf showed shiny streak signs on front is what prompted me to look, no visual of any bugs