Sad plant and inexperienced grower ):

too much water, bro! let the plants be!

looks like an over water issue, or the roots are bound up, start of root rot... I hate to say it, but I went through a similar spot. I aerated the soil. waited an extra 2 days from regular feeding, and fed with a mix of Golden tree, Piranha Juice, and changed to a foliar spray with the Cal Mag, once that week, and then 7 days later. gave the Piranha Juice a chance to work its magic.

I would say your watering a bit too much maybe, and check your ph levels both in the run off and water. Also if you think your ph is correct, make sure if your using a meter that it’s calibration is correct still. I’ve pulled my hair out before trying to fix problems like this to only find out my ph meter was off creating the entire problem from the start. Bad ph means plants lock out nutrients, as well as over watering will drown them and keep them from needed nutrients.