tips turning down, why??

hey everyone,

the tips of the leaves are turning down on my one plant. i have 2 ak47`s under a 400WHPS. temps are around 75-80 with a humidity of around 45-50. whats going on because the other plant seems fine.

Over fertilized.

soil, hydro, organic....pics? Give us something.

stress or over watering one of the two mate

could be underwatering or overwatering. If they are turning down and limp, its overwatering. If they are turning down and crisp, its underwatering. If they are turning down and yellow, you're overfertlizing.