@Sabellafella got me onto testing/dosing potassium and I couldn't be happier with my coloration.
For me, I believe it's an incredibly important element that simply lacks information about it's importance in the reef tank. Yes I can say my blues are bright but it seems to effect more than just the blue pigment alone. For example, I have an RMF Diablo Milli which is pink with a green rim and I've noticed upon maintaining my Potassium above 400, currently 420, it has taken it's pink coloration to a whole new level. The coralites literally glow... I can't fully credit potassium for enhancing it's coloration alone but I do believe it has helped color it up along with other sticks in my tank.
As for montis... My rainbow monti was starting to look like the the various shades of fall... The polyps were greenish/off yellow transitioning to a rust orange and the base was a washed out bluish grey color. Upon dosing potassium, I observed the coloration of my rainbow monti change by the day. Within 4 days I saw a dull monti gain an incredible amount of color. I have never witnessed such a drastic coloration transition prior.
I could go on mentioning the different effects that I've observed but I personally think you should check your potassium level at some point if you're lacking coloration.
