Small white hard things

[drives300]

Im sure this question has been asked several times but what are the little white crusty dots that form on everything in your tank? Are they good/bad. They are white little bumpy dots in the shape of a swirl. Is it just calcium deposits? They seem to be circle shaped.

 

[Gordonious]

They are probably tiny little feather duster worms. The genus Spirorbis are often found in, and do well, in established reef tanks. They are perfectly safe in a reef tank and can be removed usually very easily glass by razor blade or rocks by crushing them. No need to remove them though, they are all over my tanks. I just clean them off the front glass because they get in the way of good pictures sometimes.

 

[Scooter12ga]

Yup, Spirorbid worms, harmless filter feeders.

This is them, right?
http://melevsreef.com/id/spirorbid_worms.html

 

[zma21]

They are taking over my tank..

 

[jenajet]

They are good tho. I have a ton of them. Over time they seem to die down.