Mutation?

So, I'm new-ish to growing and my plant is having leaves that are turning yellow. Now I know during flowering some leaves turn yellow and fall off.

So I'm wondering if my plants are running out of food or if something else is wrong?

I have a skunk xl strain in a half and half mix of sohum living soil and the regular fox farm soil. It was all the soil I had left and I didn't have the funds to buy something else.

Sohum living soil is one of the "just add water..." soils and fox farm gives you a few weeks of food if I'm correct.

Most rookie growers feed the plant way to much and burn it. Been there done that. I don't want to burn the plant, and for all I know it doesn't need "more food."

So I noticed today that after I waterd the day before with RECHARGE that some of my plant leaves turned yellow. Way more yellow then normal tip burn or something like that. Also I should mention that some leaves are curling or maybe "clawing"

So does anyone know what is going on here? I'm trying to learn as much as I can so I can avoid all this trouble. Unfortunately I don't have a teacher locally that can show me what to do in person, or come look at my grow set up and point me in the right direction.

I'll attach some pics below.

Typically, the "clawing" is a sign of nitrogen toxicity. But, too much nitrogen also causes leaves to darken. So, without knowing more to go on, my guess is that you're dealing with a pH issue that is causing nutrient lock out.

I ph my water though. Between 6.1-6.4