What deficiency is this? GH / Ca:Mg thing?

I dose ~3ppm NO3 and ~0.75ppm PO4 daily.
.1ppm Fe from CSM+B+Extra Fe daily.
>20ppm K from KCl weekly.
50% water changes.

6.2-6.4pH and ~4dKH for >40ppm CO2. I have increased this but am using DIY so must wait. I do not use mist in this setup but L. guinea is close to the CO2 reactor. I have placed trimmings into another tank with mist and can post update.

Thank you.