What is causing the tips of the leaves to curl down like this?

Hey guys! I'm a new grower so sorry if this is a stupid question. What could be causing the leaves to curl down like this? This plant also has a nutrient deficiency that I'm having a hard time diagnosing. It appear to only be the top half of the plant. Any help with this issue would be greatly appreciated.

The strain is Cinderella99, I'm growing 8 plants under a single 600W LED (until I'm ready to move them outside). None of the other plants have been experiencing this curling or deficiency in the same way and I take care of them/feed them pretty much the same.

The only thing I THINK it could be is that the plant is too close to the light, as this plant I kinda screwed up the LST of it and not it looms taller than the rest

too much nitrogen in the food your giving it

theres no such thing as a stupid question friend

oops scrap that last one

whats it in and what are you feeding it?

go go kid said:

whats it in and what are you feeding it?

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I'm feeding it about a 1mL/L of Bloom/Grow/Micro by Advanced Nutrients (they recommend 4mL/L for "adult" plants and 2mL/L for smaller plants), a little bit of rhino skin and I just started adding Cal-Mag (1mL/L) because originally I thought it was a magnesium deficiency. I feed it roughly a waterbottle full (500mL) every 2-3 days

It's in a 1gal pot with some soil specifically made for Cannabis from my local garden center