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Death to Fungus Gnats


Hi guys,

I'm having a lot of trouble with fungus gnats in my 30 gal setup. How do you get rid of them?!?!?? I've found hundreds in my pitchers. It's really getting out of hand.
Neem oil, pyrethrins, or orthene works well.
Do you have any pings in there? When I get an outbreak I usually add a large ping or two and in a few weeks most if not all are gone. But I've never had hundreds.

Its the best CP I've ran across for taking those guys out. Another option to try if you can "seal" the setup is dry ice, make sure and do a little reading before trying it as dry ice can be VERY dangerous if you don't follow a few very simple things. Its really cold, ie can frostburn your skin in seconds, can easily make a pressure bomb if your seal is too good.

Here is the first thread google returned to me, I didn't read it but the photo's look about right. http://www.dendroboard.com/forum/plants/25309-dry-ice-pest-control.html

There are probably a few TF threads about it also a few of us have used it in the past with good results.

Its not a prefect system, it will not kill spider mites and some other spider species, it will not kill some of the tiny aphid species, it will not kill anything that lives in heavy/thick soil like mediums (the gas just doesn't penetrate I guess), it will not kill anything in an egg sack or similar. So repeat dosages can be helpful.

I have in the past gotten a one time growth spurt after each dosage, considering it is CO2 that makes sense.
@RSS no pings unfortunately, but I'll try that dry ice trick. Thanks for your help.

Neem oil, pyrethrins, or orthene works well.

When you apply these would you dissolve them in water and just mist the plants?
Bacillus thuringiensis serovar israelensis (Bti) will take care of the larvae without harming your plants or pets.

You can find this at any hardware or garden store in the form of Mosquito Dunks. Just take a small chunk and float it in some water overnight and water the affected media with the treated water. Undissolved pieces can be reused. The larvae ingest the Bti which produces a toxin which blocks the stomach lining of the larvae which starve to death. Somewhat specific to several families of insects. Since you can have fungus gnats in 4 stages of life (eggs, larvae, pupae and adults) you should treat long enough to affect all generations that might be present - 4-6 weeks.
It's easier just to put up a few sticky yellow squares. That makes a big dent in the population, if not eliminating them completely.
It's easier just to put up a few sticky yellow squares. That makes a big dent in the population, if not eliminating them completely.

There is only one plant in the tank that does't kill bugs, yet I have to go and buy artificial traps to kill them. :-))
Great suggestions both by Warren and RSS.

Like RSS said, a moderately large Pinguicula will quickly solve any fungus gnat problem you may be experiencing. I added one to a 30 gallon tank that was overrun with gnats, and a couple of weeks later it was littered with them, solving the problem.

I still have some in my Nepenthes area, but I find them in the pitchers so often that I don't worry about it. Although I also added a small P. agnata and D. regia to quickly catch any stragglers.
Bacillus thuringiensis israelensis the active ingredient in mosquito dunks works well though it is not an "instant" fix. Soak a dunk or part of a dunk overnight in the water you will use for your plants. Use the "infected" water whenever you water. That particular type of bacteria will kill off the larvae.
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Thanks so much for your help guys. I'll try some of these methods one the little buggers.
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The neem oil and pyrethrins are usually in a pre-made insecticide, the orthene is mixed into water. The latter seems to kill anything I get stuck with, save for these mystery black/white-spotted insects that act like slow springtails....
As mentioned above, Mosquito dunks are usually a good method too.