Red spots on hammer coral

[KG0986]

can anyone help me with these red spots on my hammer. My hermit crabs seem to like to go bother it and pick at the spots

 

[Uncle99]

If it don’t blow off, looks like deep red coralline.
I have three different shades.

 

[KG0986]

If it don’t blow off, looks like deep red coralline.

No it doesn’t blow off. I even scraped softly it a little and it didn’t come off. Just want to make sure it’s nothing to worry about