Day 9 Flower Black Dhalia

She's a handful. Day 9 of flower. Growth seems to have halted big time, but there's more root growth?? She seems to be using lots of nitrogen too. What else?
Dwc ppm 1550 pH 5.8 room temp 74-77 rh 45% GH 3part nutes with H2O2

Black domina.... Lol no murders around here!

looks okay but could use some cal mag to get rid of that yellowing.

I was thinking this as well. But I haven't been as attentive to this freebie as I am my regular babies.