Interesting snail hitchhiker

[Hypnotoad]

Looks like a coral. ID?

 

[Hypnotoad]

.

 

[Hypnotoad]

Bumparoony

 

[KJ]

Hard to tell from the pic.

 

[Chrisanthellae]

Could be blue clove polyps? If so be careful, they multiply even faster than GSP or Xenia and can be almost impossible to get rid of!

 

[reef lover]

Could be blue cloves or sympodium.