Could it be that since I’m watering from the top and it’s hitting all the algae and dropping the ph? Like I said my runoff was 6.7 and I’ve been feeding at 5.8??
It's possible, and algae will also consume nutrients, effectively starving your plants. How often are you fertigating? IME the 4" cubes get waterlogged, heavily, so you have to fertigate often otherwise you lose oxygen concentrations quickly, and while the media is designed to have an extremely high surface area for air, without the flow of solution through it, oxygen will be depleted quickly.
That was one of my biggest complaints when I was running them in a F&D, and will never use them in such a setup again. Those cubes seem to be designed specifically designed for top feed with regular, short intervals so the air and and solution is consistently being replaced and kept stable.
One thing I'm curious about, did you buffer the rockwool before using it? I know this is a contested concept, but I've found some credence in at least a couple hour soak in 4.0 solution before use. Otherwise, like unbuffered coco, it can be a problematic media.
Mine are actually not much different.
This is the runt though. I can’t pick up the rest to look.
Never really have.
This one looks hella sus to me. That brown color is unnatural for rockwool. It looks slimy, like there's a bacterial infection in it, which could explain why it's a runt, and explain some of your other issues which really look like the roots are suffocating (same as overwatering).
