help with pink and red pigmentation

[atrain]

I am having trouble with some red and/or pink corals retaining their color. I have had no problem with blue, purple, green, yellow, but I have struggled with red/pink. even so, I have a orage digi, and pink milli next to each other. the digi is dark orange, and the milli has turned beige. I have red planet and pink/green stylophoro next to each other, the red planet is peach and stylo is pink. ,my sunset monti is turning pale as well. I have 40+ pieces, and only struggling with these colors. alk/calcium good, nitrates and phosphates 0, and trying to increase. I have decreased water changes from weekly to once monthly, removed gfo, skim drier, which has helped all my other colors except pink/red. lights run from 20kish to 12-14kish back to 20kish over course of the day(ati led powermodle). I have tried dosing K and I, based on red sea calcium uptake calculation, but only did so for 2 weeks, and didn't like doing so, as I wasn't testing those elements. Any thoughts?