Leaves from branches partly yellow and curl up

[video=youtube;3TzGQEwxC-s]http://www.youtube.com/watch?v=3TzGQEwxC-s&[/video]

This issue affects only the second and third nodes brances on one of my plants. Those leaves shouldnt be affected by lamp heat because they are much lower then the plants canopy.
The main stalks leaves on the top has yellow tips to but it has been like this on 3 of my plants for a while now and doesnt change to the worse so it is okey I guess ?

this is what I use and do:
Plant is 4 weeks old, 1 week into bloom, ak47 autoflower hybrid (auto viking ak 47)
400 watt hps not cooltube 30-40cm from top canopies
Got a fan that blows across the canopy of my plants
25-28 degree C
humidity is usually around 50-55. Right now when I filmed it was 63 but humidity always skyrocket right after I water which I did a few hours ago.
Water 2 times a week when it gets dry
Started using nutes 1 week ago, using 3-1-4 1/4 dosage 1 week ago and 1/2 dosage today.

Issue started 1 week ago before I started using nutes.

Overall all my plants look very healthy as seen in picture though.. so what gives?

Looks like a deficiency of some kind tbh, see if it gets any better /stops happening when nutes are being used

Looks like heat stress to me.

are brances and smaller leaves more sensitive to light and heat?

Tbh heat stress isn't too hard to fix if it is that, but I doubt it is. Seriously mate just keep an eye on it and see how it goes once nutes come into play, could be plant is in need of more nutes because it is flowering

blazedaway91 said:

Tbh heat stress isn't too hard to fix if it is that, but I doubt it is. Seriously mate just keep an eye on it and see how it goes once nutes come into play, could be plant is in need of more nutes because it is flowering

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Ye maybe so, all in all the whole grow looks to be in pretty good shape... and no one plants is perfect right?

Nope not at all my 2 are 5' almost ready to harvest, with a lot on, and many fan leaves have discolouration, its going to happen. If you can finish a plant with all leaves perfect then you are a herbology expert keep it going dude, there looking good

I think mg def may be a good shout tbh, Epsom salts will fix that, but see how the nutes take effect first, over-nuting is worse than under nuting.

Popcorn900 said:

Mg deficiency.

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The nutes I use have Mg along other common micro nutes, why does this only affect one plant so heavily? I got 7 plants and all of them gets same tratment except 2 which is a bit outside of the lamps reach so they are a bit smaller.

Too many variables to say.this might help. I say just give them some epsom salt and see if they respond.
One more thing it is hard to see the leaves properly when you got that sodium on. In video you always get the lines and in pic you can't see color, makes it hard to really see what's going on with those plants.

Thanks for the input guys =)

No problem, I wouldn't worry on it too much, its a minor. As popcorn said, Epsom salts is a good shout, but just keep doing what your doing and see what happens. Don't expect them leaves to regenerate though, as they won't. Keep an eye on everything else