Coralline or GHA?

[boxster1990]

Thanks for your help? I’ve noticed green all over the rocks with small specs of purple. Is this coralline?

[Dprosser4]

Looks like corralline. Try to scratch it off with a tooth brush or something and it doesn’t come off easily it’s definitely coralline. Sometimes green takes off first and then the purple catches up 

[brianinak]

my coralline on dry rocks also started off as light green and has darkened as system matures

 

+1 to if it scraps off GHA if not coralline algae

[1891Bro]

The purple is. The green is not. Not gha either. Someone smarter than me can give a go ahead on the green stuff. 

[KNelson]

My dry rocks turned green as well.   I just thought it was algae stain.  

[Dprosser4]

9 minutes ago, 1891Bro said:

The purple is. The green is not. Not gha either. Someone smarter than me can give a go ahead on the green stuff. 

Coraline can be many colors not just purple. Green is actually pretty common and there is everything from bright pink to dark green even orange coralline. It just so happens that purple varieties grow particularly fast and are most common in reef tanks

[1891Bro]

12 minutes ago, Dprosser4 said:

Coraline can be many colors not just purple. Green is actually pretty common and there is everything from bright pink to dark green even orange coralline. It just so happens that purple varieties grow particularly fast and are most common in reef tanks

That’s all correct. But the green on those rocks is not corraline. 

[KNelson]

Mine looked just like that in its very early days.  The snails would go over it and it would still be bright green.  Now it's a bit darker and completely covered, but fortunately the coralline is starting to take over.