What is this Algae?

[atul176]

Tank info:
Currently battling dinos and am making decent progress due to more hair, coraline, and film algae showing up.
In range of reef tank parameters apart from phosphates which are elevated to encourage Dino competitions.

Description: this algae looks like brown dots, and i can’t blow it off or use a magnet to remove it. The only way I removed was by using my fingernails to scrape it away. It’s kind of like a brown calcified algae. I attached pics below, and Idea what these are #reefsquad ?

 

[lapin]

In my tank the brown dots turn into coraline. Best to wipe them clean as soon as you see them or before.