I made a mistake....when I said low nutrients, I meant very low NO3 and PO4.

I have noticed high amounts of either will surely brown/dull out vibrant colored polyps.

I feed the tank very heavily and have lottsa fish poop for my tank size. I run a probiotic system to keep up with the waste. I am getting colors like I have never seen before in my polyps using this method.

I guess I should have said- I run a fairly high nutrient, but very clean tank to get vibrant reds/pinks.