I dont think it is the fan to be honest, although im no expert, the fan is pointing upwards not directly at the leaves and I rotate the plants to keep them growing straight instead of curving toward the strongest light, so the leaves dont stay near the fan for more than a day before the plant is rotated 180 degreesThat small fan next to them in the pictures seems to be drying the leaves nearest, there will be enough air flow in your grow by pointing your fan at the lights or the wall.
If this is impractical due to space requirements or your trying to keep temps down then i guess it will be hard to make this a consideration.
Just my guess