Spray or produt to kill gnats but leave my good bugs/worms/microbes unharmed? Or is it too late?

Hey Farmers!

My question: Is there any product that would be safe to apply that will decimate the fungus gnats, but leave my good bugs (and worms) ok?
Or am I better off biting the bullet and spraying, drenching, fogging the gnats to death right now, and just getting more good bugs to keep the pests from coming back?

I am doing a fairly small medical organic indoor, LOS grow, and I recently spent around $100 on introducing predatory mites and rove beetles
. This was because I have been having issues with fungus gnats.
But in the time it took me to place the order, get the order, and then release the good bugs, my fungus gnat population has EXPLODED.

It went from being kind of annoying, to now they are everywhere, landing on my sticky buds, always hovering over my mulch layer, its gross.

I am about to harvest the last of a few plants in flower, and since I dont spray any oils during flower, now is my chance. All my girls in veg have these little bastards buzzing around them.

If I peel back my mulch layer I see lots of mites (the good kind) and some spring tails (not worried about them), but I dont see any rove beetles, despite having bought enough for 2x the sq ft. of my grow area. I dont want to kill all these mites and other possibly good bugs, but I cant take these gnats much longer.

I have tried and had very limited success with: nematodes, mosquito dunks, sticky cards, and previously spraying neem as part of an IPM to keep adults landing on the soil low
Letting the soil dry out a ton isnt really a good option in living soil, or atleast in my experience it had led to some bizarre nutrient fluctuations and kills my worms.

I am currently considering : goGnats (cedar oil), or tanlin (tdrops), and if all else fails I am ready to use some spinosad or other 'heavy' organic pesticides

Thanks in advance farmers! Your knowledge is what makes this community great!
 
45 views and no one has an opinion on this?

I think I will try and capture some of my beneficials, then root drench and neem the shit outta everything. Repeat for a week or more... then introduce my bug cultures back
 
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Liquid BTI !

Dry version/pellet is not cheaper in any way per weight and application . The expiration date is also 2+ years on the liquid version and if you pick the 1 gallon version ( other versions are like 4+ the charge ) this stuff 1 dollar a oz , it’s .5ml and you only have to apply it every “ 14 days” I apply it every every other Rez since it’s a alive based thing and you cannot ever over do it and you will never hurt any the other based things ( besides the bugs ) . for me can you handle .5ml and something that’s 1 dollar a oz? I def can ( I think they even payed for the shipping )

When I started doing this method with using BTI on every other Rez .5ml BTI every gal ratio ( killed 99.99% of my populations, I see like 1-10 adults every 1-2 months , where it was def worse and I had To apply other defenses to lower the populations )


( please note I am in No way advertising , just trying To be helpful community member ! )

High infection :
You have to remember that the BTI only kills the eggs, you need something to kill the other stages and stuff to slow it down.

*To stop the the fungus gnat from breeding/wanting to be there( def a good defense )


Look into azaguard (2x the rate of azamax and without the nasties , same price too )
Drench and foliar both ( In)till 6th week
 
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The Mosquito Dunks are BTI so not sure why they didn't work for you. They also make Mosquito Bits, which is the same thing, but just in gradual form (which makes it easier to apply for nats as you don't have to break up the dunk) and is approved for organic farming. Bti produces toxins which are effective in killing various species of mosquitoes, fungus gnats, and blackflies, while having almost no effect on other organisms.

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@mancorn Yeah I might have been a little lazy about breaking up the chunks, I thought that if I just soaked in my rez for long enough it wouldnt be an issue.. I now have a dunk soaking in each dehuey drain bucket and am adding fresh pucks to each change.

@Burned Haze

Cool I will definitely give the liquid version a shot, at least with bacillus (Bti) I am just adding more microbes to the soil and not gonna hurt my other good bugs. Thanks for the product info, I was getting sick of trying to break up pucks when I top dress and I didnt think it was necessarily doing a great job anyhow.
Ill get the liquid and give it a couple weeks before I go heavy products. Azamax is great but I am trying to keep my predatory insects alive, they also will definitely die to azamax. I just flipped the lights and feel comfortable adding azamax till week 3 so I have a little time

Sick set up in your sig Burned, that looks super good. I cant wait to grab some LED lights, the summer heat is approaching! Mind plugging a brand that you would recommend?
 
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@mancorn Yeah I might have been a little lazy about breaking up the chunks, I thought that if I just soaked in my rez for long enough it wouldnt be an issue.. I now have a dunk soaking in each dehuey drain bucket and am adding fresh pucks to each change.

@Burned Haze

Cool I will definitely give the liquid version a shot, at least with bacillus (Bti) I am just adding more microbes to the soil and not gonna hurt my other good bugs. Thanks for the product info, I was getting sick of trying to break up pucks when I top dress and I didnt think it was necessarily doing a great job anyhow.
Ill get the liquid and give it a couple weeks before I go heavy products. Azamax is great but I am trying to keep my predatory insects alive, they also will definitely die to azamax. I just flipped the lights and feel comfortable adding azamax till week 3 so I have a little time

Sick set up in your sig Burned, that looks super good. I cant wait to grab some LED lights, the summer heat is approaching! Mind plugging a brand that you would recommend?
the brand I would support for so many reason ( after using it and talking to them more ) Timber LED

I may run 3 brands of led’s, but timber is def my favorite or what I recommend if anyone asks :)
 
Just curious, which nematodes did you use? I've tried several BTI products, none really did it.
Arbico Organics SF attack was the only thing that really yielded me appreciable results. I dosed pretty aggressively, but 2 applications kept me clean for the duration of the crop.
 
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