Dude, WTF. 5.8-6.0 is way too low. That is like, hydro dude People need to stop spreading misinformation around lol.
You said you are using Distilled water with no nutes? if you are using Distilled water and not giving them nutes... thats probably the problem. I also think you are over watering. in all of your pictures, your plants are SOAKED. they are way too wet, even if you just watered them.
lay off the water and let them dry out. May have to wait as long as a week if the roots are really damaged.