Should I flush my coco?

[Thatdude84]

I noticed that my plants are not doing the best with nutes. So I'm thinking maybe I should flush them and replace with new nutes? I don't know much so anything will help lol. I'm growing 2 white widow autos , and 2 candy cane autos in coco. I'm also growing in 5gal fabric pots. How much straight ph water ships I give them and then how much nutes do I replace with? Here is some pics of my symptoms

 

[gr865]

Mix half rate nutes and pH, run at least the volume of your pots, one gallon pots one gallon nute solution.
I normally run 2x solution through the pots, i am in fabric 2 gal pots.

GR