Just one leaf so far affected anyone know what it is wrong?
@bandit Looks like some light burn mate, a drop of water got on the leaf and it refracted the light like a magnifying glass and burned the leaf, it can happen sometimes.
It looks like its only in one place, so I think that's the most likely cause. Did you foliar feed recently when lights were coming on? Or maybe the leaves are building up condensation during dark hours creating water droplets on the leaves.
Increase fan speed to prevent that from happening mate 
All in all, nothing too much to worry about, just keep a close eye on anything else like that popping up
"Keep away from people who try to belittle your ambitions. Small people always do that, but the really great make you feel that you, too, can become great.”
― Mark Twain
@macky ah I watered last night maybe a bit splashed. I thought it might be thrips.....freaked lol
more context would be helpful @bandit. Medium? What kind of nutes? Temps? RH? Light? Air circulation?...
@galandil hi its a soil grow.. apparently organic nutes from hydro store humidity has ben 30 to 40 light is at 30 to 35000 lux starting week 2 flower tomorrow. Plenty of light breeze nothing extreme and extractor fan.
Could it be thrips?
if its just the one no need to panic looks a mature leaf and they do go off colour ,could a drop land on it? or it may of got a little damp at lights off ? 😎 Replys will come bandit
@woolieback hey there hope you are right cus I am scared to go to bed if its a bug I won't sleep. Seems similar to thrips huh.
@bandit your on the ball , think that big leaf may of been under the other at some point possibly and they sweat kind of when they touch and make a sweat patch 🤣 Honest a leaf is rh 100 ,, Defoliation ? or move them apart the choice is yours 😉
@woolieback haha well don't know about a sweat patch but as Macky pointed out could be I splashed it watering last night. Time will tell if its bugs 😥 . Nice to hear from you. I will post tomorrow in my thread start of week 2 flower pics.
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