Hello everyone!

As the title says I'm a noob, first time grower. A little background information on my plants. They were given to me about 3 weeks ago. They had already started growing and when I first got them, ranged from 5 to 8 in high. I have 2 sativa and 2 indica I have no idea what strains or if they are auto flower or not.

What I've done: I transplanted them into 5 gal pots, used some very good garden soil and mother earth potting soil. I use RO filtered water and used (I know some people say its taboo) miracle grow veg food one time mixed in the soil. My big issue is the sunlight (security reasons). On a good sunny day get only about 6 hours of direct sunlight. My 2nd issue is I'm noticing some yellowing on the leaves (see pics). I'm assuming its because of the RO water but as stated, I'm a noob. Youtube has been a good reference but most videos seem tailored to indoor grow and that is not an option for me and I'm not sure how much of a difference the process is.

I appreciate any help / advice this community can give me!