gnats- flood n drain - solutions? - neem oil?

couple months old in veg, leaves are going faint green/ yellow, drying up along with branches. new ph'd res with h202 and a couple drops of bleach now and then.

i have gnats which i think might be my problem, so as i'm in 3" netpot with 1"rockwool and supercourse perlite in a flood n drain i was thinking of a neem oil drench, yet that would mean the neem would stay in the tub and some would drain back to the reservoir.

is there a problem with adding neem to your res?
any other safe liquid gnat killer?

thanks
-dan

I would try the yellow sticky traps first. That might get 90% of them and the few left over won't do much damage. Neem in the rez can't be good.

will give it a go but most of them are the tub latched onto the roots, which i figure their eating resulting in dead branches

can you put 1" of sharp sand on the perlight/rockwall or will this mess the system up?

sharp sand kills the larvae

A few mosquito dunks placed in a fine media bag would add some continued protection from larva.
Then the usual glue traps for the adults.

7CardBud said:

A few mosquito dunks placed in a fine media bag would add some continued protection from larva.
Then the usual glue traps for the adults.

Click to expand...

mosquito dunks wouldn't do any damage to nute solution/ plant if dropped into res/ tub housing roots?

can only really find this as in australia

EasyGrowerUk said:

can you put 1" of sharp sand on the perlight/rockwall or will this mess the system up?

sharp sand kills the larvae

Click to expand...

i dont even have 5mm of room in my netpot, filled to the brim with perlite, pretty sure it will start to clog up my flood n drain piping as it falls through and around the netpot. will use it if i'm ever in coco or soil

I used to add the mosquito bits to my hempy buckets and never had any issues.

The only issue I could see would be the substrate where the Bacillus thuringiensis is contained clogging things up.
That's why I suggested a fine media bag to contain it.

If you search, BT is used by many growers to combat gnats with no ill effects to plants.

The item you linked is a surfactant that drowns the adults and pupae, it won't work on roots.
Look for something that has BT in it. It should be available in some form in your area.

7CardBud said:

I used to add the mosquito bits to my hempy buckets and never had any issues.

The only issue I could see would be the substrate where the Bacillus thuringiensis is contained clogging things up.
That's why I suggested a fine media bag to contain it.

If you search, BT is used by many growers to combat gnats with no ill effects to plants.

The item you linked is a surfactant that drowns the adults and pupae, it won't work on roots.
Look for something that has BT in it. It should be available in some form in your area.

Click to expand...

great, thanks for the info.
have found Bacillus thuringiensis in a power form, will see how it goes.

Tanlin

just had this problem and it got a little bad before i noticed. still finished the round, but had to dump all my veg. the sticky yellows caught a bunch, but it wasn't enough on a daily basis for me to think much of it. Then I noticed some plants i recently put into flower were lagging and looking sad. Pulled them up to check roots and saw those little suckers crawling all over my roots. So then I checked my red solos in veg and saw all the larvae at the bottoms. Then my tester flood tent had big portions of them around the drain plugs. You can kill all the flyers, but you need to kill the larvae at the bottoms to end the life cycle. If it's been a while, then odds are they are already breeding in the bottoms and it's hard to kill them all without using some harsh stuff, which will end up burning your plants anyways... Now I cleaned everything and am just hand watering a couple daily and checking for any signs. I found a few in my beans I popped yesterday, but I also saw the larvae they used to be a few days earlier and that was after i flushed them with a water/root cleaner formula which burned them anyways....

My point is you can def get rid of alot, but never truly all the larvae unless you use really harsh shit or just start over

These work good if you have a spot you can put them 24/7 where it wont shine directly on plants. Trust me the light will attract them from far & wide. I have one in my "lung room" between my flower & veg rooms and haven't seen gnats or other bugs for that matter unless they're dead zapped on this thing. It conveniently is placed where my doorways are too so any bugs coming in cant resist it and just get zapped dead.

I quit buying preventative sprays and bug traps a long time ago. I do still keep some Plant Therapy by Lost Coast around just in case.

1ml per gallon of 29% H202,no larva will live through that.

I used this in my DTW res with no issue.