Whats coming out this rock?

[Shastri Sookraj]

Hey...need help with ID got this stuff excreting out of the LR? Looks like calcium but what's moving it?

 

[rookie07]

It's a worm. Beneficial. Uses sand to build a "shell" type of casing.

 

[Shastri Sookraj]

Thanks, I was thinking it could be a worm but was not sure if it was that or some type of reef ants.

 

[gpscuba]

I have them in my tank so far no issues