I have 1 out of five doing the same exact thing also, the other four are flourishing and have no visible signs of any probs, all same strain(damn good bagseed) all same height, same soil, same feeding schedule, everything, I flushed the shit out of her last night, i need to give her one more nite to dry up, but i have seen lil improvement in one day, so mayb.
But i was thing mayb the genetics in this one particular plant, may be bad also. There is NO discoloration on any leaves. just the curling and clawing. Also i swith my fan from static to oscilating every other day, but not directly on plants. If anyone figures this out, seems like more than one person watching this thread will benefit from someones results,