Fungus gnat experiment #569

FmSwayze said:

Are still sourcing your medium from the same place?

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Good question. Yes I do. When I was trying other methods to rid myself of gnats I would soak the new soil with BTI when fresh out of the bag and into the pots. I would do this every 3rd feed for 2 months straight. I tried doing this at the same time I would do all my other rooms/tents to see if I could kill them all at once.

#1 - They never all died
#2 - They never stopped coming back

So here I am trying different experiments to keep them out of my pots. I have many pots and many tents. I keep explaining to the BTI advertisers that I do not have a small scale grow and to stop giving me advice I didn't ask for.

But of course the know it alls come back with their 3 plant gardens and their infinite wisdom of the universe and say they are right and I am wrong.

Do you have a journal on here?

I had the little flies before a vacuum cleaner is a good tool one with a long pole ..shake the pot if any flies pop up hoover them up
I took about an inch of my soil off with the vacuum
You defo wanna target top of the soil

So far so good. Time will tell.

Experiment # 569 has failed. Holes were too big on the mesh and that was the smallest screen I could find. Bugs partied in the bottom of my pots again. But I did not give up.

I started searching for a small mesh that worked for doing bubble hash. I figured there had to be some mesh that I could use to wrap around my pots. I did a search for 200 micron mesh and bubble hash mesh. After about 10 minutes I found something I've never seen before.

Mesh bags for paint cans.

Experiment # 570 began.

I found mesh bags for 1, 2 and 5 gallon paint cans. I ordered a bunch of the 2 gallon ones and crossed my fingers. The paint bags have an elastic top that holds tight to the sides of the pot. A few pics of how they cover the pots :





I put them on the already infested pots and it works like a charm. They can't get back in, and they can't get out as well. They all wind up going back to the top of the soil. (The ones that got out during installation) I then spray my IPM on the top of the soil, feed the plants, and let water drown the rest of them on the bottom.

There is no escape. Death to bugs making homes in my pots.

These things are reusable and will last quite a while. They cost less than $1 each and are totally worth it for solving my problem with using pesticides. I will be using an IPM tho from now on even before I drop my clones in soil. The bugs are coming from my Terracraft soil bags so I will start using IPM right off the bat on all new soil when I fill up the pots.

I will kill any eggs before they hatch and if they do hatch they wont make homes in the bottom of my pots anymore. I like the IPM because it kills any mold or fungus development on my clones and soil. The IPM plus the bags will hopefully solve the bug issues. I'll give this 2 weeks before updating.

Small update. The bugs are freaking out. They are a lot smarter than I thought. They are trying to get out by the elastic part. They fail. The ones on the outside are trying to hook up with the ones on the inside. Easy kills with the sprayer.

I've noticed a huge decline in the cloud that comes out when opening the tent. At least 50% in 2 days. At this rate they may be gone in a week or 2. It is much easier to deal with the bugs on top of the soil than the ones hiding in all the holes on the bottom.

I found a huge cemetery of gnats in the rear back corners of my tent. No idea why they went their to die but it made me smile.

Have you tried any deterrents in addition to this physical barrier, like cinnamon or neem seed meal? Just curious

@Samwiseman420 i have a suggestion but it has only work for me in coco dtw and its bti also

Meanwhile in gnat/thrip world the bugs are dying off very nicely. They have no more places to hide. I spray the top of the soil every 3 days and it takes care of the ones that are left.

The only problem left are the escapees. Dealing with them on a daily basis. Getting them to zero in a perpetual grow is going to be a bitch but these bags are helping tremendously

No place for hidin' baby.............................no place to run!!!

You pulled the trigger of my.........

LOVE GUN!!!!!!



Thousands dead. None can withstand my power

and no stankin' BTI

For the dudes saying BTI, it just doesn't work for everyone. I use it every watering, I buy the microbe lift brown shit by the gallon, it helps for sure, but they're always there. If I stop using it they will be a lot worse.

I'd been using mosquito bits for 2+ weeks every day or every other day but was still seeing fungus gnats, they're driving me insane so I'm trying another method.

To my logic that's not any different to my usual set up I've always used in flower.


So I've no real concerns but I'm keeping a sharp eye on them tbf they're fine.

The ones that don't get stuck in the moisture surface tension are easy squished....hopefully before they've laid eggs, fingers crossed.

I do two things. First i put a layer of perlite across my coco at the top, the thinking being there is no big open wet spot to attract the gnats. Then i use one of those dbl sided sticky cards that i peg to the pot. With that I don't have any issues. I never really see them put I know they are there cause a carpet of gnat corpses builds up on the cards.

Update on mine. Still have adults flying around. Especially on top of the soil. I have no idea where they are coming from. They are also INSIDE of the bags all trapped and going nuts. I'm scratching my head trying to figure out how they got there. I think they may be hatching from inside the soil and getting out thru the holes in the bottom of the pots. Then they crawl up the sides of the pots and get stuck there. The ones on top of the soil may be hatching close to the top. Otherwise I'm clueless on how they are getting where they are.

The leaves are awesome tho. Not a mark them. Most likely because I'm spraying every 3 days and killing the babies. I'm going to keep that up for another week and then I have to stop because of the buds.

Getting sick of them tho. Wonder how the mushroom business is these days?

Crap I was hoping that would work. Bti aint killing them enough but its better than nothing. And I got PM Im having so much fun right now!

Some people have had success with things like beneficial nematodes or predator mites. Once established, they should continue to work. Maybe someone who’s gone this route can chime in with a suggestion ?

I didn't take dates I didn't think it too important, so my times are only approximate.

It's been a month min since I put the last coco pouches into that bag, in the last 3/4 days 2 gnats have hatched.
That was after previous use of bti, h202 and ipa @20% sprayed onto the surface lightly, it certainly kills larvea but you need to go easy with it.

I tried it as a root drench @20% but I wouldn't go there tbh, if you over do it the plant will wilt badly and maybe die, the plant i tried was still living after 2 weeks but not recovering so I binned it, maybe when I've time and a spare plant I'll test 5/10/15% ipa on larvea under the microscope then through the coco if that finishes them?

medidedicated said:

Crap I was hoping that would work. Bti aint killing them enough but its better than nothing. And I got PM Im having so much fun right now!

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Well I'm not saying this experiment failed quite yet. I've only sprayed the plants 2 times so far and tonight will be my 3rd spraying with the Capt Jacks. The leaves are really great looking and I don't see any larvae or leaf damage anywhere on the plants. I will spray 2 more times after tonight and then stop completely on the leaves. I don't want to spray the newly forming buds too much. I will continue spraying the top of the soil for the adults or eggs for a few more weeks until they are all dead or I give up the game. Gnats are one thing but these thrips don't fuck around.

The paint bags are working exactly as intended. They are keeping the bugs from getting in from the bottom and holding the ones that hatch inside the pot from getting out. It is also possible that the tiny baby thrips can escape those bags if they are hatching from the soil. I think I will be able to tell in a few more weeks.

I also bought some bubble hash type screening for my smaller pots and cut out a bunch of 4.5 x 4.5 squares. This is 110 micron so not even little tiny thrip babies can get in or out. Only water.



Once the soil is on top they hold in place very tightly and nothing can get in or out of the pot from the bottoms.



I'll be planting a bunch of seeds tomorrow and the waiting game begins. I would like to ultimately prove that the bugs are coming from the soil and no matter what I do I will never be able to get rid of them fully.

Awesome, thats my main issue is them getting in. Im in dtw coco floraflex one gal pots switching to fabric as the incredible root bound might also be causing rot.

Wondering if the paint bags or panty hose would work better. As for the PM I just was stubborn and didnt believe in circulation, hopefully. Thats whats threatening my existance right now. Just back to growing for shits n giggles.

I could be messing it up adding chlorene one said it can kill the bti but it clearly still worked but its two wks since only using bti no chlorene amd theyre getting worse. Its weird how it gets almost completely under control but then they just take over again.

The chlorene didnt kill the hyopsis miles bugs whatever theyre called which seemed to help too. Thats the thing if I could see hmiles bugs in large numbers and that not eradicate the gnats makes me think..