Is this corraline on my Astrea snail?

[Der]

Just wondering what's growing on my Astrea's shell. It's very purple in appearance but has bubbles as well. Just wasn't sure if this typical for corraline or it's something different entirely?

For reference, the rest of my Astrea snails have some green hairlike algae.

Thanks!

 

[Troylee]

Cyanobacteria.. blow it off with a turkey baster

 

[Reefkeepers Archive]

Probably just cyanno