I think the buffers in the OF have been used. YOU NEED TO CHECK PH. (PH can vary from day to day in tap water over 2 full points at my house!)

I agree with possible root bound.

Instead of fertilizer repot to larger container with more fertilizer...i.e., Fox Farms Ocean Forest soil, which you are already using.

They look nitrogen toxic to me in the pictures also. Other than that, the form looks like you are doing a good job..........Move the light a little closer too.