Alien in the Tank?

[cpllongjk]

What the heck do you think this is?

I noticed these encrusting where a sps frag plug was removed. I never saw anything pop out of them until just today. They've been on the rock for months.
The rock was "caribsea life rock" which was completely inert. These things were introduced on a frag plug from ORA corals. The shell appears to be hard and the "thing" inside looks like some type of worm that goes in and out of the shell. In this picture its coming out of the shell a bit.

 

[Sharkbait19]

Can you get white light pics? Almost looks like a really big vermetid.

 

[cpllongjk]

Can you get white light pics? Almost looks like a really big vermetid.

Heres a better picture, more white...

 

[Sharkbait19]

I’m thinking vermetid.
Wait for more experienced members to give their input though.

 

[EeyoreIsMySpiritAnimal]

Definitely vermetid snails. Either scrape them completely off the rock (outside the tank) and make sure you rinse well in tank water or glue the openings with super glue.

 

[Spare time]

Definitely vermetid snails. Either scrape them completely off the rock (outside the tank) and make sure you rinse well in tank water or glue the openings with super glue.

Or crush them with vengeance like I do

 

[EeyoreIsMySpiritAnimal]

Or crush them with vengeance like I do

But if you do that in the tank, the snail can escape and build a new tube...