What are these ??

[oliverw953]

Hi,

I have noticed these little red spots appearing on my rock, forming on a few other rocks too.

Just wondering what they are? Is it algea?

 

[I never finish anythi]

Possibly sponges . Take a pic under white lights

 

[coraler07]

could also be coraline algae, but need another pic to be sure

 

[Munns!]

That totally coralline algae which is a great sign of a thriving reef tank