I've seen green, orange, red, deep red, purple, light purple, yellowish purple, plating purple, "digitata" deep and light purple.
In a tank that is at least 6 months old... if you keep your alkalinity high, your pH stable, your lights mid range and not high... also if you keep high calcium and magnesium levels, that will help tremendously.
IF you want to grow a ton of coralline, dose Kalkwasser or "lime water" which balances your Calcium and Alkalinity levels perfectly. keep high magnesium levels and do regular water changes to replace trace elements and you will see a TON of growth. I can turn a 6 month old tank purple in 2 months...