Atari is exactly right. There are different species and they have their preferences for lighting spectrum and intensity. One species will not change into another but it does tend to produce a base that is easier for other species to populate on top of. That's why it can seem like they change colors.
I had some Marshall Island LR
that had green coralline. It also had an awesome dark purple that only thrived in the shade. Anything dark purple exposed to my MH
's died off rather quickly. It only lived in the shaded areas.
You have to think like a farmer...if you want corn, ya gotta plant corn seeds. If you want wheat, ya gotta plant wheat seeds.
If you want pink and red coralline, it's a good idea to scrape pink and red coralline algae in front of a powerhead to spread the spores. If you don't already have any of those colors, it's a good practice to borrow a rock from a friend and scrape.
However, if you want it to really take off you need to keep your calcium and alkalinity parameters balanced and phosphates low as well.