What kind of damage can gnats do to the plant? i know the larvae eat the roots but how about the adult ones that have wings? Do they eat the leaves maybe? or suck the juices out of them creating those brown spots? i also wonder if its the nutrients doing that. i did flush my plants until the run off water was at 6.8 ph. but that was 2 weeks ago and this problem is still continuing. Ill just water them instead giving them nutes and see what happens.

Do you have pics by any chance?

I don't grow in soil, I use hydroponics but I think 7.0-8.0 on PH is way to high. In hydro it should be 5.8-6.3 PH. Maybe soil is different but hope that helps. It looks like nute burn to me or a high PH level in your water.

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King David was hit by a rock and knocked off his donkey. . . he was not STONED OFF HIS ASS.

yeah i grow in soil and i think the runoff water from soil should be between 6.2-6.8 also when i water my plants with nutes i make sure i ph it to 6.8

I read that in soil pH should be from 6.5-7.0, so I'm on the borderline, but it should be alright. It's better than it was from my tap water, at least.

Fungus gnat larvae eat the little root hairs on your plant when fungus supplies are low. This is supposed to look like some kind of nute deficiency, but a lot of fungus gnat threads I've read don't report any damage. The adults look like normal fruit fly type gnats, and the larvae are little tiny white or clear wormlike things that crawl around and live in your soil. If you aren't seeing any gnats, I wouldn't be too worried about them. I don't have pics or I would have posted a thread earlier. I was gonna try to change my water systematically before i resorted to buying a camera and asking the forums.

If your pH is ok plain water sounds like a good idea. Hopefully things will improve.

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"Well, you know what they say...a JPEG is worth 1,024 words" -www.toothpastefordinner.com

Yeah i am just going to flush them and just water with plain tap water and see if things improve.

Good luck!

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"Well, you know what they say...a JPEG is worth 1,024 words" -www.toothpastefordinner.com

Thanks mate. I hope your plants get better as well.

420ben i have the same problem every cyle. i start noyicibg the brown spots 3 weeks in to 12/12. this is my 5th grow and there back right on scheduel 3rd week. i have posted and tried to find out what it is. mostly folks say its magniseim def. or rusty fungus.or to flush. i have tried many things. the good news is your buds will be ok. its seems to be astetic problem. im sure you will loose a lttle weight but i always make to the end. if i find out i will pm you and let you know. or if you find out hit me up. good luck

thos plants are seriously burned, dont feed them nutes for weeks