Yellow-Brown Leaves

Looks like rust fungus. It usually happens on the lower leaves for me. I cut those leaves off and it goes away.

Stop spilling your feed water on your plants

Hey there, can you provide a bit more information on your water? RO versus tap water? Filtered tap water? and what nutrients if any? Any pH of runoff or pH of water/nutrient solution? Would be very helpful in finding the issue! -dan

Check the pH of the runoff - as you are growing in soil you want your pH levels to be between 6.0 to 7.0 - I personally stick to around 6.3 Also, what type of soil are you using? I've looked up your feeding chart and it seems kinda high. Unless you're using some kind of light mix then most of the soils should already be high in nutrients for this stage of growth.

Looks like a PH issue in the root zone to me.

Not a lot of information to work with to help. So it's a shot in the dark on any answer. I would check my ph first off. Then feed amounts if you are feeding. If not it is likely time.