Live rock getting colour on it

[EC24]

my live rock from Haiti has been growing some purple colourations on its surface since I got it just last week. I hope this is a good sign and that the rock is doing well. Should I expect this colouration to continue and elaborate on the surface of the rock ? let me know and whats happening here. thanks. EC.

[Bertsch]

Purple coloration is good, it should bea hard substance, one which you should not be able to 'dust' it off from the rock. Where ever there is the purple substance on the rock is where the green and other alge will not grow. At the moment, I cant think of what it is called, its in one of my books at home, but this I do know, it is good for it to be there, it means other bad alge will not overtake that portion of the live rock plus IMO it adds color to the tank as well.

Generally if your able to grow coralline agale then you system is off to a good start. Additionally it will do better under less intense light as opposed to halides although it will eventually coat your rocks even under halides, just takes longer. I have done best keeping the water with adequate stronium, calcium and magnisum levels up a bit and running lots of actinic lighting. As mentioned earlier where it grows algae will have a hard time growing, looks pretty cool too!