I was using heavy nutes on both, so i'm assuming over fertilization locked out some nutrients.
I water heavy once in the morning. This could also be it since rockwool cubes can sit a couple days without water
Same technique as this one and clearly she's better
I forgot to drain the rockwool cubes after the 5.5 PH pre soak so I'm pretty confident on the over watering. It says rockwool should contain 20%-40% water weight. My cubes were saturated to 100%.
I squeezed out the additional water and I will update if they recover.