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Fungus Gnats


Teal Smith
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Whatsup Guys :)

Been a little off the radar lately, been super busy. So the grow has been going well and most of the girls are looking good (pls excuse the lighting in some photos). Unfortunately we have had a ton of fungus gnats in our area for the last month or so and they seem to have made it inside the tent (1st  photo shows the leaves yellowing w/ brown spots - only a couple plants have this happening). New growth looks okay.

IMG_9497.thumb.jpg.e88e147d2425aae881a700dca15ee995.jpg

 

 

I assume they are fungus gnat larvae but am not entirely sure - I can't get a photo because they move too quickly. They look like little worms/maggots, long and thin. Whitish, about 2mm long. I noticed them 2 days ago when I began to water. As the water drained down through the coco, I saw quite a few of them moving about in the water. When the water drained completely and they touched the coco's surface, they jumped around a few cms and then burrowed under again... Almost all pots have the larvae 😞

 


Besides bug barriers on intake and exhaust, towels under the doors, organic insect spray around the windows and doors outside the building, manually squishing them, I have followed the treatment below for the last 48 hours (also been keeping the temp low and RH as dry as possible):

* Oct 19 - Added 3ml of 50% strength HYDROGEN PEROXIDE per 5L of water and gave along with nutrients as the girls needed to be fed and watered that day.

* Oct 20 - Sprayed the surface of the coco with BioGrow's PYROL. 40ml per 1L @ 60ml per small pot. I sprayed liberally until surface was wet, and covered the base of the stem too.  I avoided leaves and buds very carefully. Since then I've found out that Pyrol only kills the eggs and flying gnats, not the larvae 😞 I suppose it will kill the gnats as soon as they emerge. If the peroxide doesn't kill them.

* Oct 21, today, pending - (some plants are very dry and ready to be watered). My current plan is to add 4ml of peroxide, increased dose, per 5L of PH balanced water and water them as usual. I will also be mounting some sticky cards horizontally the the medium surface.

 


Anyone care to share how they deal with fungus gnats? Could I be doing anything better or differently (besides the obvious prevention)? I did prevention-spray several times before flower with a product called "Buddi All-Rounder" but not much of it went onto the surface of the coco so was clearly ineffective.

Today I discovered a Margaret Roberts product called "Biological Mosquito Insectacide". It kills the larvae too. Wish I knew of it earlier! Ordered it today but will probably only arrive in 2 days. Could I be doing anything in the meantime?

Thanks guys!

(Below pics are auto GSC, LSD, AK x Critical Mass, UK Cheese) 


 

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Edited by Teal Smith
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Whatsup Guys :)

So the grow has been going well and most of the girls are looking good (pls excuse the lighting in some photos). Unfortunately we have had a ton of fungus gnats in our area for the last month or so and they seem to have made it inside the tent (1st  photo shows the leaves yellowing w/ brown spots - only a couple plants have this happening). New growth looks okay.
IMG_9497.thumb.jpg.e88e147d2425aae881a700dca15ee995.jpg
 
 
I assume they are fungus gnat larvae but am not entirely sure - I can't get a photo because they move too quickly. They look like little worms/maggots, long and thin. Whitish, about 2mm long. I noticed them 2 days ago when I began to water. As the water drained down through the coco, I saw quite a few of them moving about in the water. When the water drained completely and they touched the coco's surface, they jumped around a few cms and then burrowed under again... 
 

Besides bug barriers on intake and exhaust, towels under the doors, organic insect spray around the windows and doors outside the building, manually squishing them, I have followed the treatment below for the last 48 hours (also been keeping the temp low and RH as dry as possible):

* Oct 19 - Added 3ml of 50% strength HYDROGEN PEROXIDE per 5L of water and gave along with nutrients as the girls needed to be fed and watered that day.

* Oct 20 - Sprayed the surface of the coco with BioGrow's PYROL. 40ml per 1L @ 60ml per small pot. I sprayed liberally until surface was wet, and covered the base of the stem too.  I avoided leaves and buds very carefully. Since then I've found out that Pyrol only kills the eggs and flying gnats, not the larvae  I suppose it will kill the gnats as soon as they emerge. If the peroxide doesn't kill them.

* Oct 21, today, pending - (some plants are very dry and ready to be watered). My current plan is to add 4ml of peroxide, increased dose, per 5L of PH balanced water and water them as usual. I will also be mounting some sticky cards horizontally the the medium surface.
 

Anyone care to share how they deal with fungus gnats? Could I be doing anything better or differently (besides the obvious prevention)? I did prevention-spray several times before flower with a product called "Buddi All-Rounder" but not much of it went onto the surface of the coco so was clearly ineffective.

Today I discovered a Margaret Roberts product called "Biological Mosquito Insectacide". It kills the larvae too. Wish I knew of it earlier! Ordered it today but will probably only arrive in 2 days. Could I be doing anything in the meantime?

Thanks guys!

(Below pics are auto GSC, LSD, AK x Critical Mass, UK Cheese) 


 
IMG_6778.thumb.jpg.c6ef9afb991620a513cf8b06f15e540a.jpg
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Hey bud. Try sprinkling cinnamon powder on the surface of your medium. You can turn the medium a few mm deep to work in the powder.
I use cinnamon powder mixed in my soil and do not have gnat problems. Ever.

Sent from my DRA-LX5 using Tapatalk

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Also in the running is Diatomacious Earth. But I know that has to be applied to dry medium only. I could apply that tonighth and stretch the watering until tomorrow morning. Not sure if 12 hours will be enough for the DE to kill the larvae...

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@DamDave Sounds good. Though, does the cinnamon have to be dry to work or can it be watered in? I ask because a couple of the girls are super dry and need to be watered tonight still
You can add before watering. Then tomorrow turn over a few mm of the top of your medium. That will disturb the nice warm moist area the gnat fungus likes.

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Cheers Dave, thanks so much. We hardly have any cinnamon left so will hit the pots w some Diatomacious Earth tonight, then get cinnamon 1st thing in the morning, sprinkle, and then water again with hydrogen peroxide. Hopefully theat combo will be okay. That's the current plan

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Bro your plants are gorgeous, so much variety you are in for a treat. When I've have fungus gnats my first goal is to dry out that top layer of soil, gnat larvae cant survive in dry soil. 

Next thing is a top dress of Diatomacious Earth, I personally use Karbadust but alot of growers object to it so rather use DE if you have it.

Main thing with fungus gnats is to make sure that top layer of soil isn't wet for long periods of time, that is their breeding grounds.

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@Bakstein420 Thanks man :D 

Top layer of soil is dry - check
I'll layer on some DE tonight, turn lights off as some plants are really dry and I'm noticing some leaf tips curling upwards as of about 2 hours ago, so figured having the lights off would be good.

 

Some plants can't wait much longer as I've already been drying the pots out for 2 days.

Yes, you're right - they must have laid their eggs about 2 weeks ago, after I watered, while there were about a trillion of them flying around outside (and some inside LOL). I swear I've never seen so many, they were just hanging out at every entrance waiting to come inside.
 I have been watering every other day for the last 5 weeks or so. I let the pots go from wet to almost completely dry before watering

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30 minutes ago, Bakstein420 said:

Bro your plants are gorgeous, so much variety you are in for a treat. When I've have fungus gnats my first goal is to dry out that top layer of soil, gnat larvae cant survive in dry soil. 

Next thing is a top dress of Diatomacious Earth, I personally use Karbadust but alot of growers object to it so rather use DE if you have it.

Main thing with fungus gnats is to make sure that top layer of soil isn't wet for long periods of time, that is their breeding grounds.

Thanks Baksteen :) I'm excited to test drive them. 

I have something called Eco-Dust, basically calcium carbonate powderized. Inert. Sounds like it could be similar to Karbadust. 

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10 hours ago, Teal Smith said:

Whatsup Guys 🙂

Been a little off the radar lately, been super busy. So the grow has been going well and most of the girls are looking good (pls excuse the lighting in some photos). Unfortunately we have had a ton of fungus gnats in our area for the last month or so and they seem to have made it inside the tent (1st  photo shows the leaves yellowing w/ brown spots - only a couple plants have this happening). New growth looks okay.

IMG_9497.thumb.jpg.e88e147d2425aae881a700dca15ee995.jpg

 

 

I assume they are fungus gnat larvae but am not entirely sure - I can't get a photo because they move too quickly. They look like little worms/maggots, long and thin. Whitish, about 2mm long. I noticed them 2 days ago when I began to water. As the water drained down through the coco, I saw quite a few of them moving about in the water. When the water drained completely and they touched the coco's surface, they jumped around a few cms and then burrowed under again... Almost all pots have the larvae 😞

 


Besides bug barriers on intake and exhaust, towels under the doors, organic insect spray around the windows and doors outside the building, manually squishing them, I have followed the treatment below for the last 48 hours (also been keeping the temp low and RH as dry as possible):

* Oct 19 - Added 3ml of 50% strength HYDROGEN PEROXIDE per 5L of water and gave along with nutrients as the girls needed to be fed and watered that day.

* Oct 20 - Sprayed the surface of the coco with BioGrow's PYROL. 40ml per 1L @ 60ml per small pot. I sprayed liberally until surface was wet, and covered the base of the stem too.  I avoided leaves and buds very carefully. Since then I've found out that Pyrol only kills the eggs and flying gnats, not the larvae 😞 I suppose it will kill the gnats as soon as they emerge. If the peroxide doesn't kill them.

* Oct 21, today, pending - (some plants are very dry and ready to be watered). My current plan is to add 4ml of peroxide, increased dose, per 5L of PH balanced water and water them as usual. I will also be mounting some sticky cards horizontally the the medium surface.

 


Anyone care to share how they deal with fungus gnats? Could I be doing anything better or differently (besides the obvious prevention)? I did prevention-spray several times before flower with a product called "Buddi All-Rounder" but not much of it went onto the surface of the coco so was clearly ineffective.

Today I discovered a Margaret Roberts product called "Biological Mosquito Insectacide". It kills the larvae too. Wish I knew of it earlier! Ordered it today but will probably only arrive in 2 days. Could I be doing anything in the meantime?

Thanks guys!

(Below pics are auto GSC, LSD, AK x Critical Mass, UK Cheese) 


 

IMG_6778.jpg

IMG_6771.jpg

IMG_9496.jpg

IMG_9478.jpg

IMG_9479.jpg

IMG_9480.jpg

IMG_9481.jpg

IMG_9486.jpg

IMG_9465.jpg

IMG_9470.jpg

Fungus gnats are a tricky one, especially if you are so far into flowering... And by the way those buds are looking amazing man! Really nicely done. The easiest way to rid your self of fungus gnats is let your pots dry until your plants cant take it anymore 5 - 7 days or so. And then be careful not to over water, because they thrive in damp conditions. Then once dried up etc. the pyrol for me worked like a charm even for the larvae. But I did notice I was never really completely rid of the problem, they still out and about, but definitely got it under control. Also be sure there are no wet spots in the tent from watering and stuff, it does mean more work but it will help.

Again very nicely done. Those plants seemed to grow over night... Trying my hand at Autos currently. Well 1 Gelato bin Laden from President seeds I got for free. Think ill start a report.

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4 hours ago, ORGANinc. said:

Fungus gnats are a tricky one, especially if you are so far into flowering... And by the way those buds are looking amazing man! Really nicely done. The easiest way to rid your self of fungus gnats is let your pots dry until your plants cant take it anymore 5 - 7 days or so. And then be careful not to over water, because they thrive in damp conditions. Then once dried up etc. the pyrol for me worked like a charm even for the larvae. But I did notice I was never really completely rid of the problem, they still out and about, but definitely got it under control. Also be sure there are no wet spots in the tent from watering and stuff, it does mean more work but it will help.

Again very nicely done. Those plants seemed to grow over night... Trying my hand at Autos currently. Well 1 Gelato bin Laden from President seeds I got for free. Think ill start a report.

Hey Organinc, thanks bud :) They got big so fast man, the first time I've worked with autos, so I was surprised at the speed :) The LSD from FastBuds is particularly impressive.

They've been dry as a bone for 1.5 days now. Pots are now super light and some the plants are drooping alot. The plants that have yellow and spotty leaves are being hit the hardest by the gnat larvae and those are especially feeling the dryness, with some leaf tips curling up as of yesterday afternoon. 
I dimmed the lights lower last night to avoid overdehydration, say 1/3 power, and early this morning switched lights off completely, ready to water now...

Should I hold on longer before I water?? A couple plants are looking like they might be getting damaged from being so dry. I'm not sure if they'll make 7 days of dryness, not sure exactly how long I can take them before doing irreversible damage....  The fabric pots are real small, only 5L and so they dry out pretty quickly.


Looking forward to hearing about the Gelato BL :) :)

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8 minutes ago, Teal Smith said:

Hey Organinc, thanks bud :) They got big so fast man, the first time I've worked with autos, so I was surprised at the speed 🙂 The LSD from FastBuds is particularly impressive.

They've been dry as a bone for 1.5 days now. Pots are now super light and some the plants are drooping alot. The plants that have yellow and spotty leaves are being hit the hardest by the gnat larvae and those are especially feeling the dryness, with some leaf tips curling up as of yesterday afternoon. 
I dimmed the lights lower last night to avoid overdehydration, say 1/3 power, and early this morning switched lights off completely, ready to water now...

Should I hold on longer before I water?? A couple plants are looking like they might be getting damaged from being so dry. I'm not sure if they'll make 7 days of dryness, not sure exactly how long I can take them before doing irreversible damage....  The fabric pots are real small, only 5L and so they dry out pretty quickly.


Looking forward to hearing about the Gelato BL 🙂 🙂

Yeah thats what I was thinking, as you are in flower and surely want to make the most of the bud gains, So yeah I don't think its worth it risking the yield, especially if the girls are in the prime. 

I would water bud, maybe just leniently. I also hear silica also wipes out the larvae but not sure how true.  

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Nice one, thanks for confirming, bud.  I feel watering the desperate ones now is the right thing to do also. I'll go easy on the volume of water, so that they can be ready to be watered again tomorrow.

As luck would have it, I have been adding some silica to my nutrient solution for the last week or so. I'll keep up with that :)

Thanks man :) I'm sure they'll be okay. They are adult and close to finish, so I think I'll be okay.

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@PsyCLown Hey bud :) Yes, I thought of using Neem as a last resort too! trying hard not to 

For now it's been H202, Silicone Plus, Diatomacious earth and dryness, and will follow up with something I ordered yesterday - Margaret Roberts Mosquito Inscetacide (Bacillus thuringiensis). It'll arrive tomorrow so I'll keep you posted on how well it works. It's meant  to get rid of them completely, in all stages of their life cycle. I'm considering using cinnamon as well but I think between these things and less water, it should do the trick

OTN I'll be watering even less from now on. Looks like I'll have to give in to watering every day. I was trying to get away with watering every other day for time saving purposes but even that seems like too much, hence the gnats...

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Nice one, thanks for confirming, bud.  I feel watering the desperate ones now is the right thing to do also. I'll go easy on the volume of water, so that they can be ready to be watered again tomorrow.

As luck would have it, I have been adding some silica to my nutrient solution for the last week or so. I'll keep up with that :)

Thanks man :) I'm sure they'll be okay. They are adult and close to finish, so I think I'll be okay.
You can also water from the bottom with trays, your medium will suck up the water and you can leave it dryer on top to get rid of the larva

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3 hours ago, Teal Smith said:

@PsyCLown Hey bud 🙂 Yes, I thought of using Neem as a last resort too! trying hard not to 

For now it's been H202, Silicone Plus, Diatomacious earth and dryness, and will follow up with something I ordered yesterday - Margaret Roberts Mosquito Inscetacide (Bacillus thuringiensis). It'll arrive tomorrow so I'll keep you posted on how well it works. It's meant  to get rid of them completely, in all stages of their life cycle. I'm considering using cinnamon as well but I think between these things and less water, it should do the trick

OTN I'll be watering even less from now on. Looks like I'll have to give in to watering every day. I was trying to get away with watering every other day for time saving purposes but even that seems like too much, hence the gnats...

I believe this should work well, never tried it myself though.

However the adults I believe still need to be controlled.

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