corraline?

[rickycobra]

I am a little confused about this corraline thing. I have a few spots on my rocks throughout my tank. I just bought a few new peices and they have really good color to them. Tonight I noticed that more is starting to spread, but I have also noticed that I have some pale green spots starting. The green spots look as if they are starting to change to purple as wel. Is this normal, I am using ro water, but dont have a calcium reading yet. Will buy a test tom. Thanks for the help, ricky

 

[katfish]

Trick to get it to spread more and faster is to either change the flow from your powerhead to make contact with the rocks that have the most corralline or actually scrape/brush off the rock lightly while in the tank.
I have a test now-I am adding only Seachem Reef Builder to my 90 aggressive with nothing else other than regular water changes and have seen pretty good results so far.