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Fungus Gnats Are Killing Me!!!

Hi People
 
I have been fighting fungus gnats for a while now and have seen some improvement but i want to run my fight past you all to see if im on the right track or what...
 
I have about 20 starts going and they seem to be doing good for the most part. I lost 3 due to the gnats, i think...
 
They are in 3 x 3 pots in potting soil under lights with a fan on 24-7.
 
Based on 2 weeks of weighing one pot ive been bottom watering 2 times a week, which i thought was alot and still wonder but they start to look rough if i push it to a once a week. About an inch of water for a 25 minute soak.
 
They are all about 6 weeks old.
 
On january 8th i started soaking 1/4 mosquito dunk in my water 24 hours ahead of watering and has helped alot. I have sticky traps all over the area and they help. I know the whole point is to stop the reproduction process and wait out the adults that live a few weeks. 
 
I also added 1/4 inch of perilite to the tops of all pots. Today i have potato slices on all pots and will toss in a day or so hopefully with alot of youngsters on them.
 
Ive tried everything shy of hydrogen peroxide which id rather not do.
 
 
So i guess Im asking if im on the right path and just still in the bugs life cycle or what? Am i doing something wrong?
 
Help!!!
 
Thanks all!!
 
Thanks guys!

I guess im also wondering if i continue the dunks until they are gone or what. Any input is great.

And yeah they suck
 
Thanks hophead. Yeah ive been dunking for almost a month and ive got sticky traps all over the plant area. Guess im doing all i should be!
 
Bottom watering, mosquito dunks, perlite topping, sticky traps...perfect. I also recommend a loose layer of pure peat moss under the perlite as a topper. A good fan to quickly dry the surface after watering and spacing out your watering as long as you can without hurting your plants are good measures that it sounds you may already be using...lastly you could get some beneficial nematodes and they'd be toast in short order. What kind of soil are they in? Just curious because the years I had troubles mine were in some not so great soil and I suspect the soil was already infested.
 
Sarge said:
There is absolutely nothing wrong with h2o2. Its just water with an extra oxygen atom which will bind it self to larvae and destroy their bodies. I've used it and it has been the solution.
 
Thanks Sarge, it might come to that. Im worried about it hurting the good stuff in the soil. Is that a valid point?
 
 
stc3248 said:
Bottom watering, mosquito dunks, perlite topping, sticky traps...perfect. I also recommend a loose layer of pure peat moss under the perlite as a topper. A good fan to quickly dry the surface after watering and spacing out your watering as long as you can without hurting your plants are good measures that it sounds you may already be using...lastly you could get some beneficial nematodes and they'd be toast in short order. What kind of soil are they in? Just curious because the years I had troubles mine were in some not so great soil and I suspect the soil was already infested.
Thanks stc, i figure I'm doing all the right stuff but i thought they would be gone by now. I was looking at the beneficials last night. Do they just go into my water? Its miracle grow with some added perilite. I know its not the best. They were either in that or on the one freaking basil plant i didn't spray when i brought it in but that dried out regularly so I'm kinda thanking the big orange store at the moment for the gift.
 
I've been using mosquito dunks in my water since November when I started this years grow. I've had a few but never an infestation like I did last year. Using mosquito dunks full time is cheap insurance IMHO.
 
A layer of perlite? 1st time I've heard that suggested. Is it supposed to work like sand, or is there some other reason it works?
 
Jeff H said:
I've been using mosquito dunks in my water since November when I started this years grow. I've had a few but never an infestation like I did last year. Using mosquito dunks full time is cheap insurance IMHO.
 
A layer of perlite? 1st time I've heard that suggested. Is it supposed to work like sand, or is there some other reason it works?
 
Like sand yes. Its supposed to be a layer the larva can't get food from. Id say it helped. Everything IS helping i just hoped it would be over now that i have annuums in my sprout chamber.
 
Years ago (30+) when I had reptiles we used a product called "Shell-no-Pest Strips". We use to let them air out for twenty four hours, and then cut a 2 x 2 piece off and stick it in a margarine cup with a lid and some holes poked in it, and then put it in the cage. Always seemed to keep the mites off my snakes.
 
So recently I found something called Hot-Shot Strips at Home Depot. They seem to be the same thing. I just let it air out for twenty four hours then I hung it over my seedlings about a foot and a half. I was doing this more as a precaution due to not wanting something slipping in from the out doors, as I had a really bad last year of critters, and I am still fighting the Thrips on last years plants. 
 
What amazed me was the hundreds of tiny dead bodies all around my seedlings. Yep fungus gnats. I did not even know I had them. This stuff really works but I really don't know how safe it is near plants. My plants seem to be fine fine and it does not seem to have harmed them in anyway. 
 
Since then I have corrected the problem for future seedlings. It seems the gnats were more interested in my bottom potting soil and not my top seedling soil. So in a effort to save a few bucks I only used a spoon full of seedling soil on top in the center of the cup. The potting soil was exposed around the outer rim of the cup.
 
Upon closer examination I could see this is were the gnats were going. Once I went back to covering the potting soil with a 1 inch layer of seedling soil the gnats seemed to leave my cups alone. I use Jiffy seedling soil on top, and I think it might be to dense for the gnats to burrow. Never thought of the Mosquito Dunks. I will be putting that one in the vault.
 
Good stuff SL3. Thank you for all that. At least in a few weeks if I'm still in the battle i have a few more things to try. Good Good stuff!
 
PrimeTime said:
Good stuff SL3. Thank you for all that. At least in a few weeks if I'm still in the battle i have a few more things to try. Good Good stuff!
Note: Warning label on this product says it should not be used in an area where it is occupied more than 4 hours at a time. As my set up in in an outside cargo container this is not an issue for me. But if your set up in in your family room, I would not use it. 
 
I didn't see if it was mentioned but those pesky gnats also lay eggs in the side + bottom drain holes. Otherwise i'd also say you are on the right path.
 
SL3 said:
Note: Warning label on this product says it should not be used in an area where it is occupied more than 4 hours at a time. As my set up in in an outside cargo container this is not an issue for me. But if your set up in in your family room, I would not use it. 
 
Well its in my kitchen so the 4 hours would be pushing it on the safe side, but its also where the grub comes from....ill look into it. Thanks again!
 
Jetchuka said:
I didn't see if it was mentioned but those pesky gnats also lay eggs in the side + bottom drain holes. Otherwise i'd also say you are on the right path.
 
 Thasnks Jetchuka. Not sure what else i can do in that situation. I pick up the pots and dustbust the tray everyday, its my beer #2 event  :flamethrower:
 
And i just got home early as the roads suck and found one in my annuum germ chamber, spray those with dunk water. Gotta be kidding me!
 
I hear you! I started seeing gnats a couple months after first planting. It was ok at first, I would just kill the ones I noticed, and it wasn't a huge problem. Then I got lazy and the population blew up. I've been working on this for several weeks now with limited results. Just when I think I've got them defeated, it seems like another round hatches! Thinking of trying h2o2 next... keep us updated!
 
Degenerate glad im not alone i guess. If you havnt already you should try the above steps im taking. They seem to help, i mean they have to right? Im gonna go a few more weeks i guess and then might hit em with the peroxide. Good luck!
 
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