Just a note, I used dyna-gro grow for a long time, but then realized Dyna-gro foilage pro is formulated much better for MJ for Veg
Check it out
Your temps are swinging too high, you need them balanced, that causes the plant to use nutes and then conserve them with those temps.
Your plants look like they are overwatered and very droopy, what is the color of your roots? Can you take picture of it's roots?
Your plants are lacking micronutrient, the veins at the top of the plant are yellow and normally that happens to plants that lack zinc, never seen it happen before in hydro plants...... not saying this is zinc, but your plants are lacking micronutrients for one....
what is your ppm/EC with the nutes you got mixed in there now?
We need to first start on how much nutes you gotta have and then go from there.
What color are your roots? White? Brown? Are your roots slimy?
Off White
Your plants look like they are overwatered and very droopy, what is the color of your roots? Can you take picture of it's roots?