Fungus Gnats and Mosquito Dunks

[stoneypenguin]

Ive had fungus gnats for sometime now and have tried a number of things to reduce them, but the bastards always come back.

Ive heard Mosquito dunks work well, but Im not sure exactly how to use them. Is it safe to feed them directly to the plants? If it is how much should I use per gallon for it to be effective? (there no recommendation the package for watering plants directly with it.)

Or should I have just have an open water container in the room let the adults find the stuff?

UPDATE:

I ended up breaking up 1/4 of a dunk into 2 gallons of distilled water, let it sit overnight, and just flushed with the stuff. I was due for a flush at the time anyway since I had been feeding consistently for 2 weeks.

Within a day I started to notice fewer adults and now I haven’t seen any for at least 2 weeks. I was planning on following up by crushing the dunks and putting them on top of the soil, but they died so fast it wasn’t necessary. The dunks didnt have any negative impact on the plants and they seem to be doing even better after the flush itself.

I can’t confirm it killed the larva too, but I am assuming no more adult gnats = no more babies. Hoping they have a fairly short life span.

I would strongly recommend these for anyone who is having issues with gnats.

 

[LolaGal]

I could not find any info on the subject so I tried a couple things. First I soaked 1 tablespoon of dunk to one gallon of water and watered in after it soaked overnite.

Then I got tired of that and crumbled the dunk putting some dunk on the top of the soil surface, about one teaspoon of dry dunk per pot.

This worked pretty good! If you have any standing water, you can put some dunk in that too, like catch trays, etc.

No more gnats for me.

Now I gotta work on the spider mites... lol

DIE FUNGUS GNATS DIE!

 

[stoneypenguin]

I could not find any info on the subject so I tried a couple things. First I soaked 1 tablespoon of dunk to one gallon of water and watered in after it soaked overnite.

Then I got tired of that and crumbled the dunk putting some dunk on the top of the soil surface, about one teaspoon of dry dunk per pot.

This worked pretty good! If you have any standing water, you can put some dunk in that too, like catch trays, etc.

No more gnats for me.

Now I gotta work on the spider mites... lol

DIE FUNGUS GNATS DIE!

Haha, I hear ya man. Dealt with those bastard mites too. Best thing for me was a tiny bottle of Floramite from the local grow shop, wiped em out after 1 spraying, no damage to the plants (unlike neemoil). I hate bugs more than ever now.

Crumbling the mosquito dunks into the soil actually sounds like a really good idea. I just want to make sure its safe for the plants and safe to smoke after.

The plants cant absorb this bacteria in the dunks through their root system can they? Im assuming / hoping it just stays in the soil and kills larva.

 

[LolaGal]

No, plants can't absorb it. I think it is best to sprinkle on the top of the soil. Drying out between waterings does not affect this product.

 

[Phillthy]

best success for me was the 4 day method. crush an entire dunk into a 5 gal bucket and fill with water. stir and let sit over night. water with this. adults only live 4 days so any that are left to lay eggs will die off and you will water again in 4 days to ensure you kill off any remaining eggs and larva. no more gnats.

 

[Citizen024]

Can you drop them into a large res and let it sit?? I have 55 gallon barrels, and if I float I in there, leaving it in while I change res and all, will it work? I go through about 15-20 gallons a day.

 

[princess cronic]

Crumble on top. I use them all the time in my grows as well as my ponds.

 

[Phillthy]

Can you drop them into a large res and let it sit?? I have 55 gallon barrels, and if I float I in there, leaving it in while I change res and all, will it work? I go through about 15-20 gallons a day.

yes you can drop a dunk into a res.

 

[Sleepy]

you may need two for a full 55 gallons...

it is also available in liquid form: under the Gnatrol name...



"Gnatrol Fungus Gnat Control


Gnatrol is a highly selective, biological larvicide for use in greenhouses to control fungus gnat larvae. It may be used on a wide variety of ornamentals, as well as all bulb crops, bedding plants and vegetable sets. The active ingredient is Bacillus thuringiensis israelensis (Bti). Once the larvae have ingested the insecticide, protein subunits paralyze the fungus gnat larvae, which stop feeding immediately and die - usually within 24 hours. Will not harm people, pets or the environment. Mix 1-2 tsp. / gallon of water. For heavy infestations use 4-8 tsp. / gallon of water."

one websit i see it listed on says it has been discontinued by the manufacturer...

mosquito dunks contain the same active ingredient and they work very well.

i use them in my rain barrell, excellent results!

i did notice that when i used them indoors for the mary-jew-wanna, it really messed with my pH, and the plants suffered for about 5-7 days each time i applied it.

you should keep in mind:

to effectively kill all gnats you need to break the life cycle. three applications on week apart each time. otherwise, they will keep coming back and you will go crazy.

 

[LolaGal]

Good point Sleepy, Gnatrol is so damn expensive, I just thought $5 for the dunks, (I got 2 for that)was way more economical.

What happened to your pH Sleepy? Did it go u p or down or what?

I am trying to become an expert on Mosquito Dunks, been researching them for about 6 months or more, not much application advice when I started using them could be found.

That's why I try to pass on what I've found out thru personal use of Dunks.

Dunks are good stuff.

 

[Sleepy]

i'm trying to remember...i think it went way high...

 

[LolaGal]

very interesting

very interesting

i'm trying to remember...i think it went way high...

Hmmm. I have trouble with pH acidity in the MG soil I use. I noted increased soil pH as well, but attributed it to my addition of lime in the soil when mixing.

Perhaps I should do a control so I can test this out.

The dunks may be contributing to the higher soil runoffs that I wanted.

Interesting, very interesting. thanks Sleepy.

OP: What does the Floramite have in it to kill? Maybe I can find the same thing under another name around here. I have some Malathion, but I ain't used it, although it is a close thing... !!

 

[Miss Blunted]

Skeeter dunks are amazing....no more gnats!!

 

[3dDream]

dunks + traps + spinosad = f'in dead

 

[Phillthy]

lola you got me thinking about something. i never thought of just sprinkling the crushed dunk into the flower pot.

these two points stand out to me now...
# Mosquito dunks, which dry out will start working again when they become wet.

# Unused dunks will remain active indefinitely.

this would keep me from having to water twice as it will always there when watered... hmmmm


eta dunks are an organic pesticide

 

[Rolando Mota]

Dunks work but they take a while, up to a month. Spinosad is what finally did it for me, one thorough soaking was all it took.

 

[Phillthy]

the problem with spinosad is it can be toxic to other animals.

 

[dongle69]

It only takes 1/2 a dunk in each of my 100 gallon reservoirs to keep the gnats away.
My Ph isn't affected at all.

 

[Blue Dot]

the problem with spinosad is it can be toxic to other animals.

Only bees, mollusks and fish.

If you've got those in your grow room you've got bigger problems than gnats. lol

Spinosad shows low toxicity when ingested by mammals (male rat LD50 = 3738 mg/kg) and no additional adverse effects from chronic exposure. Studies on spinosad show slight toxicity to birds, moderate toxicity to fish, and slight to moderate toxicity to aquatic invertebrates. However, it is highly toxic to bees (honey bee LC50 = 11.5 ppm) and is highly toxic to oysters and other marine mollusks. Applications to areas where bees are actively foraging should be avoided. After the residues have dried, it is much less toxic to bees.

BTW, you could just buy gnatrol wdg (water dispersable ganulues) from bghydro and although more expensive probably have a much, much higher count of bt.

 

[Rolando Mota]

the problem with spinosad is it can be toxic to other animals.

Anything you are specifically concerned about? I assume you mean in an outdoor situation. The fact that it's omri listed is what sold me on it; I try to keep things as benign (yet effective) as possible.