Slug?

[Timothy Davis]

Hey everyone!
I stocked my tank with a coral about a month ago, and it had the slug from the first picture hitch hiking. Now all of the sudden.. six similar looking slugs have appeared but are much much much smaller. Did it reproduce? And are they safe? And lastly.. what is it?

 

[USCG CWO]

Stomatella snail, good guy

 

[Coastie Reefer]

Look like stomatella snails, although I've never seen one with a shell quite like the first pic. I've only seen them flat and smooth. If they're stomas, they're awesome cleaners.

 

[Katrina71]

Mine reproduce like crazy. I like them.