Too early to tell sex.

As for your leaf problem,... it's most likely nute burn since you've stated that you're using nutes on top of the MG soil which is already too hot for seedlings. Don't use anything except PH'd water on seedlings if using nuted soil. Well that's what my take on it... I don't know much about seedlings tho as I'm trying my first run of seeds (got a good deal of experience with clones, but no seeds)