Argh!!

I noticed this plant last night, and it's looking hurt! :(

All of her sisters are in top shape, it's hydro so they all get the same water/nutes... This would lead me to think it's heat-related, but it's spaced so close to the others that I don't know why only this plant would be afflicted... It is in one of the brighter areas though

What's making the leaves die and curl upwards like this? The coloring is symptomatic of a P deficiency.

BUD LUV

P.S. The last pic is of one of her healthy clone sisters

the only time i've gotten something similar to this is from letting a plant dry out so bad that some tissues on the leafs die. The dead tissues are very crispy and curl just like yours.

could that be it? maybe the hydro is blocked near this plant or something

i grow in soil