What is this?

[IsuckATusernames]

So I just started my first sw tank. I was given a 35g and it just so happened to fit perfectly in the front of my bar where I originally had a liquor cabinet thing. Today I came across something that made me finally join a forum. I don't know how to Google this so I'm asking you folks. What is this crawling around on my lr? My tank is only 6 days old and still cycling. It's definitely a hitchhiker from my lfs. I bought 40 lbs of lr because they had it on sale for $3/lb.

 

[IsuckATusernames]

BTW It looks like half a clam but it's moving around on the rocks like a snail.

 

[AdamNC]

Limpet Snail.

 

[mike werner]

limpet,he's one of the good guys I believe.

 

[reef lover]

Looks like a keyhole variety....occasionally snack on sps...