[master kusher]

I've got a fairly heavy gnat infestation and have been doing what I can to get rid of the lil buggers. (without damaging some of the plants I have flowering) hanging the sticky fly traps from the ceiling but it dosent seem to be working...they get full top to bottom in 5-7 days and I have two in the tent but I need to go pick up another pack, because I only have one hanging. I also recently started putting potatoes in the soil and I saw some dead dried up larvae cling to them but not as many as I thought I was going to see...HELP?! things are getting a little bit crazy lol

[MJPassion]

Use 3% hydrogen peroxide mixed 4:1 w H2O for a soil drench.

This will kill some of the adults & a bunch of the larvae turning them into plant food. It will not eliminate the gnats, however.

You may have to do this a few times before you are satisfied.

Also, place the sticky traps, sticky side up, next to or on top of your containers.

You will notice a significant difference in the number of flyers the first day after the drench.

[BOMBAYCAT]

I have had pretty good luck using mosquito dunks found at stores like Lowes/Home depot. I crumble 1/4 TSP and place it on the top of the soil and also by the drain holes at the bottom of the flower pot. It is not instant but it takes a couple weeks and no more gnats. The cat likes to chase them, but for me they are a nuisance.

[Chevy cHaze]

Hey Master Kusher,
Look for any product that contains "bacillus thuringiensis israelensis" or short BTI and do a watering with it. They're bacteria and will kill off the larvae pretty quick while not harming anything else.I think that stuff might be in mosquito dunks too. Key is to drench the soil with it once and au revoir gnats. works like a charm.
Not sure where you are and what products are available, but it should be easy to find out for you if you do a web search.
all the best,

CC

[DemonTrich]

Promis
2ml/gal solo cup clones
10ml/gal up pots

[Ru5tyNaiL]

If you have a lot of fliers use a vacuum to suck them up every time you're in your room, and use mosquito dunks to get the larvae.

If you get the dunks, I suggest crumbling them up and putting them in your water for your next watering but you need to let them soak in it atleast a couple hours first. I usually use it in every watering for a few days afterwards to make sure. That usually does it for me.

If you're an organic guy be careful of the h2o2, it will harm your micro herd.

[yts farmer]

Use sticky traps and see if you can buy a product called neudomück. Its a german product its very cheap and its is very concentrated so a little goes a long way.

1 small bottle sorry cant remember the correct size but about 50mm can treat 1000 litres of water.

Have a look on amazon and you might get lucky that a seller might stock it.

When i bought mine years ago it cost less than £10 and thats delivery included.

Peace.

[Muleskinner]

Assuming you want to stay organic....I use Gnatrol to kill their asses, purchased in 2-pound bags off eBay for $80. A watering of 3-4 teaspoons/gallon of Gnatrol will knock them down by 90% in a couple days and 100% after further waterings.

A great way to kill them all instantly is a soil drench with Neem oil. At somewhere around 1/2 to 1 tablespoon of Neem oil per gallon one watering kills them all. However they will come back over the next couple weeks without further doses and I find that Neem can hurt the plants when used as a soil drench. Some can take it, some can't.

Another quick killer is to cover the top of the soil and the tray under the container in a layer of diatomaceous earth. You have to wait until the top layer of soil has dried out like a crust, the DE will stay dry and they will all get killed. Next time you water the DE gets wet and stops working however, this solution gets messy quickly. It's quite satisfying though, as you spoon the DE powder onto the soil they desperately struggle and flail to get away and die.

[moses wellfleet]

Beneficial nematode steinerama feltiae. Problem neutralized!

Within 30 minutes all larvae will come up to the surface and die!

[chronosync]

Originally Posted by moses wellfleet

Beneficial nematode steinerama feltiae. Problem neutralized!

Within 30 minutes all larvae will come up to the surface and die!

(in coco dtw)

yo, while youre here,i am definitely getting some predators but i dont want them to go into a death trap (sm-90, h2o2)

ive been trying to kill them with sm-90 and h2o2 but id rather use BT and nematodes, how long should i wait to apply some nematodes?

honestly i would just flush everything and start clean but my roots cant handle it? im working on some roots but the gnats are making my plants sick and not one of them is giving me the kind of root growth im used to seeing.

not to de-rail a thread but maybe this will help OP too