leaves

The new leaves on my plant are curling very slightly on the edges. Is this a deficency of something or does it just happen sometimes. The leaves are very green and healthy looking except for this.

I need more facts. Do you ph test? What kind of medium are you growing in? Do you monitor in temp in your grow room? What is it? What kind of lights do you have? How far are they from the plants? Do you have a moisture meter? What kind of fertilizer do you use? At what strengths? Do you have a fan? Ventilation?