Fungus gnat control

[CC420710]

I am wondering what is the most effective treatment for fungus gnats and their larvae. I recently had a round with them and want to stay on top of it. I used neem at first then switched to peroxide. Trying to get something different deciding between mosquito dunks or a thuricide? Unless someone knows something better?

[s62]

Isn’t there a nematode who eats their larvae?

[CC420710]

I believe so but not sure exactly what they eat and don’t eat.

[Mr.furley]

Do your 3 parts water to 1 peroxide to kill the larvey, let the medium dry out completely, Put a half inch of perlite on top of your medium,
the larvey live in the top of the soil and can't survive in perlite alone., add yellow sticky traps by your light to catch the adults

[CC420710]

Doing the perlite on top also heard putting sand at bottom and top would help. Supposed to not be able to get through it. Anyway I have perlite on hand so seems like the best option. I bought another fan for better airflow and have mosquito dunks on way.

[Colombo]

mosquito-bits I have used with great success with control and elimination with last grow. Crushed the mosquito biscuits to a powder and sprinkled it on the top of the media and watered in. within 2 wk all gone. Used neem oil on foliage. Hope this helps . Good Growing !!

[HappyDaze]

I find fungus gnats when my air movement isn't adequate; they hate it when it's windy. If I get them in my reservoir, I stick a computer fan on one of the cup holes and blow air through for a few days and they completely disappear.

[CC420710]

Yeah I went and bought another fan with better output. The two little ones don’t compare to a bigger box fan. Thanks for the input

[alltatup]

@CC420710 I use gnatrol. https://www.amazon.com/gnatrol-Selec...gateway&sr=8-3

I ordered it for a gnat problem in May 2017, and then I had gnats again on this grow. I added it to the reservoir for 3 weeks as recommended, and put the sticky yellow papers in with the plants. Gnats gone in 3 weeks.

[CC420710]

I had to order yellow sticky traps I couldn’t find any in town which is weird. All kinds of sticky just not yellow. Anybody by chance know the survival rate of seedlings that have damage from gnats? I have a few with yellow leaves and a couple just not growing much anymore. Will they be able to survive it or are they done for? They are around 3 weeks in soil can post pictures if needed

[Cali]

Can you post some pics? Would like to see what the plants look like? Also neem once a week as an ipm will keep any pest away plus neem has NPK and micronutrients damn near can grow a plant with neem alone.. where did you get your neem?

[alltatup]

CC, with seedlings and young plants, sometimes you just have to be patient and let them bounce back. Just treat them with extra TLC and see if you can coax them to get strong. Cannabis has a very strong will to survive. ;-}

[CC420710]

Yeah I know neem works well as I used it for spider mites a while back but I remember reading that a bug can build a tolerance to a certain method so it doesn’t hurt to have more than one. Also it seems I’ve been struggling with these for a while now. I messed up and let my guard down to soon and it doesn’t take them long to spread. Posting pictures now I am pretty sure the smallest one is a goner

[alltatup]

She might still surprise you!

[Cali]

Those plants will survive. What you should do is let the soil dry up a bit and sprinkle diatomaceous earth (food grade) and that will help a lot just make sure you don’t put a fan to it or you will blow the dust everywhere and DE is good at that. Also beneficial nematodes go to tip top bio control. Com won’t be hard to find they will have pics of pest and it’s predatory mite or nematodes for the larvae in the soil. And then again there is neem lol they won’t get used to it it destroys egg and larvae stops them from eating and reproducing also it’s a good idea like you said to have different ways to fight pests because I wouldn’t get neem anywhere close to my flowering plants that’s when beneficial insect come in to play but you shouldn’t have to by the time your flowering I would just give up and start over

[CC420710]

Great advice I appreciate all the help. I have a bigger fan in there now to help. Did a neem soil treatment and spray and mosquito dunks on way just in case. I know my clones are goners since they never rooted and it’s been too long now. I will take more once gnat problem is cleared up. Is anything that works good at repelling insects indoors? I am planning to use sand or perlite at bottom and top of pot. I read they either can’t get through or can’t survive in it. I did the potato thing last night. I heard it is used to test how bad it is but I also read that the larvae is attracted to it bringing them up out of soil. If any stuff if I mention is wrong feel free to correct me as I am new

[Cali]

What are you growing in? Soil? Hydro? In living soil you can use beneficial mites or nematodes as a preventative method.

[s62]

Ahhh, is that a living soil only thing? At one point, we saw a single fungus gnat in my tent, and my mentor offered to get me some nematodes if I saw more. Never did, but I didn’t realize that was just a super soil thing.

[CC420710]

A little over two weeks. I would of waiting longer but they had pretty extensive damage from gnats much worse than the babies got. and I didn't think they could make it much longer. Plus side they were cuttings I took myself and have several clones already. Soil black gold natural, 20% peat, 10% perlite and 10% vermiculite. I was thinking of getting some nematodes for future grows

[Cali]

Not sure if its a living soil thing. What I do know is salt based nutrients or other chemicals may hurt your beneficial mites/nematodes in the soil. That’s why it’s recommended you use dechlorinated water and make sure it has no chloramines or they will hurt your life in the soil.

[Ardek]

H2O2 also kills beneficial nematodes.. so if you are using that (worked well for my gnat problem but doesn't touch the adults, so I still have somewhat of an issue) you'd want to treat with H2O2 the watering prior to adding beneficial nems.