What could be wrong with this plant?

Let me know what you think is wrong please.The one on the left is 3 weeks, and the one on the right is 4 weeks. What do you think is making the right plant's leaves look like that? They are under a 400w Mh 18/6 and in some foxfarm ocean forest stuff with some added perlite and vermiculite. They are watered every 3 to 4 days, ph is around 6.8, temp stays between 60 and 80, humidity around 30% and 50%.

looks like either a small deformity or its a little hot where ur growing, what light do uhave

early signs of mag def. maybe