Gnats in hydroponics

[alltatup]

I went over to GWE to read after I found quite a few gnats flying around in my reservoir. Which is the best application for the roots?

[OzBud]

Interesting, they're more a soil problem.
I don't know the answer but I'd be interested to know for future reference.

Have you got screens on your air intake?
Have you had them before?
Did you clean down your grow area with something like bleach in between grows?

[alltatup]

The air intake is a fan: they can't make it through without slice and dice. Never had them before, and yes, thoroughly cleaned after grow 2. I changed reservoir yesterday; when lights go on, I'll give an update.

[Sammy]

Been fighting fungas Nat's for 30# plus years these 3 thing's helped. Haven't found a way to kill all of them Over watering of easy exposure to Water makes it harder. Just my 2 ¢.

[alltatup]

Thanks, Sammy I will get the yellow sticky paper and the mosquito bits, but how do you use with hydroponics? You grow in soil, right? (Over watering is not an issue in hydro...)

[Sammy]

No dirt here. Rockwell,stonewool,and some in Coco. Depends on what kind of hydro you're using you can still over water with it. Ru bubbleponics? Bugs are such a PIA!

[alltatup]

Yes, with irrigation system goes on twice a day for 5 minutes. I never thought I'd have a bug problem, although the dirty South is certainly full of bugs!!!

[Sammy]

Good luck let us know what works I'll be interested . I've even heard of people putting Panda film over there reservoirs maybe that'll help.

[DW2]

Howdy alltatup, I had a problem with white flies and gnats a couple of years ago, but found what will stop them, Azamax. At the first sign of the little critters, I start using 10 ml/ reservoir and if there are any signs on the leaves, I apply a foliar spray to the leaves. The stuff is useable up to the day before harvest, although once it is used in the reservoir, it becomes systemic and helps stop further infestations. It is not cheap (I have found it for as low as $19/4 oz.) but it works on many different critters.

[alltatup]

Thanks so much, DW2: I just ordered some, and some of those yellow sticky things.

[DW2]

It is very strange, every time that I have put one of the traps up, the flies and or gnats vanish, but I have never found one on the traps! Maybe it scares them away, I still keep some on hand, just in case!

[NebulaHaze]

I've never used it against fungus gnats, but I've used this stuff to kill other bugs in the water before. It's a supplement called SM-90. I know it doesn't say anything about killing bugs, but someone told me about it years ago and it's worked for me. I'm not sure I believe them, but I contacted Nutrilife (the company that makes it) and they say it shouldn't harm the beneficial bacteria in Hydroguard. I would definitely change the reservoir after I'm sure the bugs are gone, and add water with Hydroguard without any SM-90