harmless to fish and aquatic invertebrates solutions to kill fungus gnats

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Hello, There is a fungus gnat infestation in my paludarium, and I'm using mosquito bits, however there are still many adult bugs flying around. what materials can I use to make a spray that I can spray the gnats with that if there is residue in the water section will not harm the animals inside?
I'm thinking rubbing alcohol but I know that is harmful in larger doses
 
If they are fungus gnats, the only way to stop them is with a parasitic worm (nematode) that you water into the soil. The worms eat the fungus gnat larvae and break the cycle. They are safe, environmentally friendly but cost a bit. I bought a small packet in Australia for $100 but only used 1/3 of the packet to treat 20 pot plants. A tiny packet mixed with some water and poured over the soil would fix the problem.

Google "fungus gnat nematodes" and order them online. They take about 2 weeks before you notice a reduction in the gnats but they work, unlike everything else.
 
A downside to a paludarium, a pile of houseplants or white worm cultures on soil is that once you get fungus gnats, they manage to stay around. Sticky traps get lots of them, air circulation via a fan really disrupts their life cycles, and spraying with a mix of alcohol and water kills a lot of them.

I have little yellow sticky traps to monitor them, and every week they catch a few even if I never actually see them around the plants. They are survivors. I have never found a miracle method to eliminate them. Colin's idea sounds great. here, it's $20 CAD on Amazon to buy some. It says not to order when there's a risk of freezing en route, so I won't order right away, but next month, incoming creatures.

It's snowing here today. Fungus gnats don't like being frozen, but neither do houseplants.
 
If they are fungus gnats, the only way to stop them is with a parasitic worm (nematode) that you water into the soil. The worms eat the fungus gnat larvae and break the cycle. They are safe, environmentally friendly but cost a bit. I bought a small packet in Australia for $100 but only used 1/3 of the packet to treat 20 pot plants. A tiny packet mixed with some water and poured over the soil would fix the problem.

Google "fungus gnat nematodes" and order them online. They take about 2 weeks before you notice a reduction in the gnats but they work, unlike everything else.
A downside to a paludarium, a pile of houseplants or white worm cultures on soil is that once you get fungus gnats, they manage to stay around. Sticky traps get lots of them, air circulation via a fan really disrupts their life cycles, and spraying with a mix of alcohol and water kills a lot of them.

I have little yellow sticky traps to monitor them, and every week they catch a few even if I never actually see them around the plants. They are survivors. I have never found a miracle method to eliminate them. Colin's idea sounds great. here, it's $20 CAD on Amazon to buy some. It says not to order when there's a risk of freezing en route, so I won't order right away, but next month, incoming creatures.

It's snowing here today. Fungus gnats don't like being frozen, but neither do houseplants.
Thanks! I'll try to find myself some worms as well.
and @GaryE , how did you prepare your alcohol solution and how did you use it?
i think these two in conjunction will help kill them faster.
 
I don't use it around the fish. With all my tanks, if the fish get into the booze, I'll be broke.

I spray the soil surface on potted plants, in a dollar store sprayer not measured carefully - maybe 30% alcohol. I don't have them in my bog paludarium, as I regularly drown the surface. My problem is worm cultures and my shade plants in pots.
 
Don't bother with anything but the nematodes. I spent thousands of dollars buying yellow sticky tape, fungus gnat soil, sprays, everything. I even went online and tried all the home remedies. You can kill a lot of the adults but unless you get rid of the larvae, you won't get rid of them. The adults breed as soon as they leave the soil and have usually bred before you see them or before they land on the yellow sticky tape. I was swapping the yellow sticky tape every 2 weeks (1 week per side before they were completely covered in gnats) and I had over 20 bits of the tape in the 1 bedroom unit.

The fungus gnats got so bad here, there were literally hundreds of pairs breeding on the ceiling every day. They were landing on me, flying into my eyes, up my nose, in my ears. They landed on food and things I was washing. I was on the phone to the suicide help line a lot because of them. After nearly 2 years fighting them I saw an episode of Gardening Australia and they had a section on fungus gnats. They mentioned everything I had tried except the nematodes. I looked online, found a place over east that sells them. Ordered some, which arrived a few days later. Used them and no more gnats. I see the odd one here and there and they are from new plants I bought, but the only way to break the lifecycle is to kill the larvae while they are in the soil and you need the nematodes for that.

This was 1 week for this plant and each plant had 1 yellow sticky tape and I had 20 more sticky tapes in the unit. There's a couple of blowflies on the tape but most of the black specks are fungus gnats.
20230914_110734-1.jpg
 
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As soon as it warms up, I'm getting some.

I imagine they would also kill whiteworms. I'll experiment.
 
The company I got mine from said they only affect fungus gnat larvae and don't attack anything else. The link below is where I got mine from. You can email them and ask if they eat white worms.

When I got mine, I added a heaped tablespoon of the powder (they come in a white fluffy power type stuff) to a 9 litre bucket of tap water (no dechlorinater needed) and stirred it up. I left it for 30 minutes before stirring it again and then pouring it into a watering can, and pouring a bit over each pot.

I watered the pot plants with normal tap water about 30 minutes before applying the worm water. After adding the worm water, keep the plants out of sunlight for 24 hours and away you go. You have to water the plants every day for 2 weeks after treatment so the potting mix doesn't dry out but you can do it less often if you live in a cooler climate like Canada. I had to do it every day here because it was 35-45C.

They recommend a second dose but I only did one.
 
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Don't bother with anything but the nematodes. I spent thousands of dollars buying yellow sticky tape, fungus gnat soil, sprays, everything. I even went online and tried all the home remedies. You can kill a lot of the adults but unless you get rid of the larvae, you won't get rid of them. The adults breed as soon as they leave the soil and have usually bred before you see them or before they land on the yellow sticky tape. I was swapping the yellow sticky tape every 2 weeks (1 week per side before they were completely covered in gnats) and I had over 20 bits of the tape in the 1 bedroom unit.

The fungus gnats got so bad here, there were literally hundreds of pairs breeding on the ceiling every day. They were landing on me, flying into my eyes, up my nose, in my ears. They landed on food and things I was washing. I was on the phone to the suicide help line a lot because of them. After nearly 2 years fighting them I saw an episode of Gardening Australia and they had a section on fungus gnats. They mentioned everything I had tried except the nematodes. I looked online, found a place over east that sells them. Ordered some, which arrived a few days later. Used them and no more gnats. I see the odd one here and there and they are from new plants I bought, but the only way to break the lifecycle is to kill the larvae while they are in the soil and you need the nematodes for that.

This was 1 week for this plant and each plant had 1 yellow sticky tape and I had 20 more sticky tapes in the unit. There's a couple of blowflies on the tape but most of the black specks are fungus gnats.
View attachment 339819
woah, that sure is a lot of gnats.
As soon as it warms up, I'm getting some.

I imagine they would also kill whiteworms. I'll experiment.
It's already warmed up a little bit here, and the gnats are going crazy!
 

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