Little white tubes? What are they?

[Mike Honcho]

I've just stated to notice this little white tubes on my rock, sand and even backs of snails. They're almost perfectly cylindrical. I have no idea what they are. Can anyone help?

Thanks!

 

[melosu58]

They are just mini dusters. They are excellent filter feeders. Great additions to the tank.

 

[Mike Honcho]

Thank you!