Leaves yellowing and curlind down

Hey, came home to this:


It looked fine this morning, like 12-14 hours ago.
From what I read it looks like over-fertilizing, can someone confirm this? Leaves are yellowing from the sides, tips curl down. Yellowing is mostly on the bottom leaves, but everything is curled


Also last couple of day were really hot, with temperatures going to 100-105, but today was a relatively cool day with temps at around 70-75. Can this also be from rather sharp temperature drop?

This is Auto AK, three weeks old. Last watered two-three days ago with clear water, not a lot - aroun 1.5liter(3/8 gallon). Before that - 5 days prior to this time, maybe liter(1/4 gallon) with 1/4 dose of nutes. Soil is also "mildly" fertilized :/ Soil is also pretty moist, so maybe water stress?

Any ideas? Don't want to cut the nutes to find that this is actually a deficiency.

You can't let it get to 100 degrees. You should be around 76-78 unless using co2. Then it would be about 10 degrees higher. Get a fan ventilation or turn the wattage down when it gets that high you have to change something!

Over watering. which is a bit odd because your fucking baking them to death.

With such high evapotraspiration rates you better back that nute shit off..way off.

When your 110 degrees do you reach for a class of warm salt water??

Yep seems to be nute burn plus 100 degrees, just water for a whole week if not more and drop the temps to lower 70's if possible for a few days, or u going to fry it, done that mistake b4 myself =)


Good luck Amigo!

-Jugz

Thanks! Well, I'll cut down the nutes. I'm quite sure I didn't overwater, but will let it dry a bit more now anyways.
And regarding the temps - it is allright now. It's just that I leave in the deserty region and sometimes there are those super-hot days which come from nowhere. And during those days it didn't show any signs of stress. Wierd shit. I'll get another fan to blow on her.

To Much "N" makes plant leaves look like a claw - reduce you nutrient amounts - your plant is to young for strong amounts of