Red corals under the typical Blue/White LED setups tend to turn orange-ish. I've experienced this with Acan lords and Blastomussa and it happened within just a few days.
The coral colors we see are based on pigments generated by the coral to reflect wavelengths. Afterall, any color you see of anything in life is a reflection of that wavelength. Early LED products were built with cool whites and blue led's. The absence of full spectrum wavelengths would certainly skew pigments and colors.
Pefect example of a LED lit tank. Leggy growth. Not fully saturated colors. Mosty millis, stags, montis and LPS. No deep blue acropora, no ice fire echinata, no solid purples, no acans grown from frag to colony. LEDs work but have limits and if you are a new reefer reading this thread you need to be reminded of the overwhelming zeal that LED users seem to have. LEDs work but have limitations.
LED's DO have limits. But it's a new technology and rapidly evolving. As I said above, spectrum range was an issue. Newer LED products addressed it. In my experience, the next issue is the unidirectional nature of LED's. They are essentially a bunch of tiny point-source lights. There isn't a lot of refraction at play. This causes a lot of hard shadows, which is a serious problem with branching corals. Plating corals don't see to mind.

This was also an issue with Metal Halides till we started using smarter reflectors. I actually switched back to metal halides for a while until I started looking at ways to solve it with LED's. Santoki's thread led to some clues, as did some conclusions of my own. I'm starting to figure this LED thing out. That said, LED's grow corals just fine. You just have to be a little smarter with them.
As for solid purples, that doesn't happen with 10k metal halides or T5's easily either. As for the other corals mentioned...
The ice fire echinata was grown out from a single polyp. Yup, a single polyp! We're talking about starting with millimeters. I have to keep an eye on that fast growing pink millipora and make sure he doesn't overshadow the ice fire. Bad placement is my fault.
My tank is no TOTM material. It's been lit with halides, t5's, and LED. It's been through a major move, and quite a few set backs. The last one was a house reflooring disaster. Long story. But I'm happy with the way things are going, and I'm happy with the colors. FWIW, I don't really like Radium tanks in person, so my idea of a good looking tank and coral color is biased to my own preferences.