Fungus gnats organic grow help

Kingrow1

Well-Known Member
Haven't had them yet in my hydro setup but not saying it can't happen just not yet lol. And as Doc says they didn't cause any damage to the plant that I could see and at one point I had a major infestation, watering the pot would have them swarming out and driving me nuts. I would hazard to guess that getting them in hydro is a lot less frequent, I'm the poster child for not taking many precautions :(.
Ive heard they are worse in hydro as they can penetrate the medium better due to increased air, coco and similar products seem to suffer worse than soil which is reasonably impenetrable to them.
 

Kingrow1

Well-Known Member
Haven't really been able to find the mosquito bits here since it is winter but I can look around more.. but still wish I could upload a picture because it seems that something else is eating away at my leaves. Can't really find much on what could be doing that anywhere
Order on Amazon, plenty of the right variety there. Maybe you have moth larvae or mites or some other leaf eaters, silver moth etc, identifying the culprit is crucial for treatment.
 

Johnny Lawrence

Well-Known Member
I've dealt with them in hydro. I don't know if anybody has mentioned it yet, but I used tanlin from CX Hydroponics. It got rid of them.
 

Budley Doright

Well-Known Member
Ive heard they are worse in hydro as they can penetrate the medium better due to increased air, coco and similar products seem to suffer worse than soil which is reasonably impenetrable to them.
5 years and nothing so touch wood lol. Hard to believe because I never didn't have them in soil lol.
 

HeartIandhank

Well-Known Member
ime, fungus gnats live THROUGHOUT the ENTIRE medium of coco, center, edges, top inches, bottom inches, the whole shebang. They mercilessly eat the rhizo fuzz leaving smooth noodles of roots.

SF nematodes works great for the gnats in my area, two days and the white worms will go dark brown and black as the todes eat the from the inside out.

The small white movers and the white worms I found throughout all my medium, not simply limited to the top few inches as I hear so often.

No combination of BTi, vinegar milk or coffee dishes, tanglefoot traps, gnatnix, and a variety of sprays would fully eradicate. Only after applying the SF nematodes that I noticed the critters in the medium started dying away.
Those combinations can, in fact, eradicate.. I've done it more than once. The problem people have with fungus gnats is the same as most others.. not properly planning, executing and finishing. I like the nematode option though if you have access to a strain that really works. Nematodes are not nearly as universal as companies who sell them want you to believe..Gotta have the right ones, from the right lab, that survived getting to you and must be applied correctly. That's why I recommended BT, traps, and pyrethrin bomb (optional, but easier).. more likely for OP to have success, imo.

What nematodes do you use? Would like to know one that really worked on Fungal Gnats. I love them for flea control in the lawn, in my region.. takes a little time, but really works. The ones I use on my lawn (Lawn Patrol Nematodes) were not effective.
 
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CannaBruh

Well-Known Member
Those combinations can, in fact, eradicate.. I've done it more than once. The problem people have with fungus gnats is the same as most others.. not properly planning, executing and finishing. I like the nematode option though if you have access to a strain that really works. Nematodes are not nearly as universal as companies who sell them want you to believe..Gotta have the right ones, from the right lab, that survived getting to you and must be applied correctly. That's why I recommended BT, traps, and pyrethrin bomb (optional, but easier).. more likely for OP to have success, imo.

What nematodes do you use? Would like to know one that really worked on Fungal Gnats. I love them for flea control in the lawn, in my region.. takes a little time, but really works. The ones I use on my lawn (Lawn Patrol Nematodes) were not effective.
Steinernema Feltiae

All of the listed suggestions do work, but they just didn't work for me. After months and months of battles, losing a few young plants I tried nematodes. No problems since. It's only an experience and isn't meant as any kind of rebuttal.
 

Kingrow1

Well-Known Member
Suprisingly cannabis buds are quite similar to those yellow sticky hanging cards, picked a few out of my bud over time...
 

Johnny Lawrence

Well-Known Member
Like I mentioned before, tanlin has worked for me when I had an unbeatable fungus gnat problem. I'm in hydro. I was going to add some more to this convo, but wanted to do a little research first - I don't like to give out bad info.

Got googly for a few minutes and found accounts of tanlin not working in soil - or, you know, people having less than stellar results. The reviews from people dealing with fungus gnats in hydro seem to be pretty much unanimous in that tanlin works. I had the same experience.

Here's what I did in hydro. I had 20 plants in 2 gallon ebb and flow buckets. I top watered a gallon into each plant with 2 drops of tanlin - I think that was the dosage. It's either one or two drops per gallon. I'm too lazy to run downstairs right now and look. Anyway, I top watered it in and let it chill for four hours - (for noobs) meaning that in ebb and flow, the water with the tanlin was returned to the control bucket, then drained to the reservoir - then changed the reservoir like normal. They were gone after one, maybe 2 treatments. Plants were unaffected. This was done in early flowering, week 1 or 2.

Now, as a preventive, I keep sticky traps outside the tents/rooms, hanging from the ceiling.
 

MichiganMedGrower

Well-Known Member
Like I mentioned before, tanlin has worked for me when I had an unbeatable fungus gnat problem. I'm in hydro. I was going to add some more to this convo, but wanted to do a little research first - I don't like to give out bad info.

Got googly for a few minutes and found accounts of tanlin not working in soil - or, you know, people having less than stellar results. The reviews from people dealing with fungus gnats in hydro seem to be pretty much unanimous in that tanlin works. I had the same experience.

Here's what I did in hydro. I had 20 plants in 2 gallon ebb and flow buckets. I top watered a gallon into each plant with 2 drops of tanlin - I think that was the dosage. It's either one or two drops per gallon. I'm too lazy to run downstairs right now and look. Anyway, I top watered it in and let it chill for four hours - (for noobs) meaning that in ebb and flow, the water with the tanlin was returned to the control bucket, then drained to the reservoir - then changed the reservoir like normal. They were gone after one, maybe 2 treatments. Plants were unaffected. This was done in early flowering, week 1 or 2.

Now, as a preventive, I keep sticky traps outside the tents/rooms, hanging from the ceiling.

Excellent post!
 
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