Help!! White round things growing everywhere

[SvenBenn]

Have noticed these small white round guys growing everywhere. On the glass, rock, snails, filters. They are hard but can be scraped off. What are they and anyway to get rid of them?

 

[lulubap]

Looks like spirorbid worms. Nice little filter feeders as far as I know.
Edit: If you're looking to get rid of them, some wrasses such as the six line might do the job. Population explosions can be result of new tank or overfeeding. Could also be overstocking.

 

[Cole.mormon]

Spirorbid worms