Fungus Gnats

Here's the problem, I've got them and i can't get rid of them!! So I got 4plants in 2x4x5 room under 9(6500k) cfl lights inline fan in and exhaust! I purchased some SM-90 and mixed 1/2tsp to gal water and have watered with it 3x. 1st time I did 2cups each plant waited 4 days gave another 2cups each waited another 4days and gave 3cups each and I still have them! I've put up yellow sticky tape which people say is to monitor gnats not treat! Wondering how people feel about putting 1.5inch of perlite on top of soil to suffocate gnats and keep them from doing what they do.. Also I would continue SM-90 I've yet to try foliar spray is foliar maybe a better option? My worry about perlite on top is i only planted in FFOF and didn't mix anything else and I feels soil stays moist already! Would a layer of perlite keep my soil too moist and create more problems? Any advice/suggestions are appreciated in advance!!!

Gnatrol and yellow sticky traps will take care of them. Gnatrol is BT variation Kurstaki and is a soil drench, it will kill the gnat larva. Yellow traps should be placed at soil level to capture the gnats as they head to the soil to lay eggs.

ive had fungus gnats before in perlite hempy grows. I hear a layer of sand works much better, but that will also make ur soil not breath as much and keep the medium too moist, which is the main cause of fungus gnats, they love a wet environment. be sure u arent overwatering and keep on them

on top of that info, people bury 1 inch cubes of raw potato replacing them every three hours or so. the gnats lay eggs there instead of your soil and you throw them away each time replaced

You didn't really specify the medium or how old the plants are? I would suggest two things:

1) Transplanting if possible and mix a lot of perlite in your soil mix. Make sure that you aren't using old soil that already has gnats in it.

2) I've put a layer of perlite in the reservoir water tray and a thin layer on the top soil. This will help somewhat. Gnats will lay eggs in the first couple inches of top soil, and also will lay eggs in any excess water in a water tray. They will also hang on in moist drainage holes. Let your plants get really dry before you water again.

mosquito dunks.. take a 1/3rd of the dunk and crush it up. spread it on ur soil, and water. should kill all gnats.

i did this in my hydro system cuz of those pesky little fuckers... the 3rd day, i saw dead gnats everywhere. its works like AIDS for africans
muwahahahahhahhahahaha

Hi there these fungus gnats can be a pain I've had a bad infestaion or two in my time first order of business would be to put something over top layer of soil to keep them from laying eggs on moist surface hydroton,sand would work well atleast a inch or so
Next try to let these plants dry out your plant will let you know when it thirsty leaves will droop a little fungus gnats infestations suck as larve eat the root hairs and starve plants

urgod said:

mosquito dunks.. take a 1/3rd of the dunk and crush it up. spread it on ur soil, and water. should kill all gnats.

i did this in my hydro system cuz of those pesky little fuckers... the 3rd day, i saw dead gnats everywhere. its works like AIDS for africans
muwahahahahhahhahahaha

Click to expand...

What a dick thing to say. Aren't you late for school little boy?

Another great product which works wonders is called Gnat Maxx. It is completely organic. I used it in my hydro setup and got rid of them in one treatment. Haven't seen a sign of them since!

use neem oil spray leaves and drench soil with 2 tablespoons of neem oil per gallon of water when sprayed on leaves turn off light intel leaves are dry and then put perlite on soil about 2 inches thick because fungus larvae should be in the first to inches of soil so remove the 2 inches of soil them put new soil and some perlite on top of that trust me this work if you really just want to get rid of the bugs for once and also use sticky fly traps

Alsystin 250 larvicide by bayer thats the shit i tryed alot of things what people say perlite ,gnatrol ,scaride drench,you name it and at the end of the day you might kill them with those drench chemicals but it shocks them a bit and they will always come back even got mate in sealed co2 room they still get in there some how, 1gram does 10litres i hit them every second week religosly even with no larvey just precaution does no harm to plants one bit it splits the outer shell of the larvercide and next watering there dead with out shell, if bad infestation hit them three feeds in a row and then once fortnight i pay $2 a gram be carfull scarid fly cary pythium .