High light, flow, low nutrients, and supplementing B is supposed to help in reds and pinks.
What kind of lighting does the seller have?
Has it always been pink/purple in your tank or did it shift to that color. The reason I ask is because pictures can be a little deceiving even if the seller didn't intend it that way. Also if it has shifted to the current color it could just be the coral acclimating to your tank. I run my tank with slightly higher nutrients than most of the places I get corals from and they tend to take on a more dull color for about a month or so before returning to their more vibrant state. Just my two cents
I find that light (type, spectrum, intensity) has a very strong influence over color. This is especially true if you're making big jumps like MH to LED. I can't trust any LED lit tank's color because it's guaranteed to change under my halides.
Red is the most difficult color to keep in my experience. I've had periods where my tank did well with red, but currently I can't get deep, dark reds. I dose Red Sea color program and still no luck. I run all T5s and LEDs. Someday I'll figure it out I hope!