Baby Snails?

[C_R_V2000]

I was looking at the tank last night wondering what sort of nocturnal inverts have taken up residence in my little ecosystem and to my surprise I saw a legion of what looked to me to be baby snails!

Can I get a confirmation on the type of snails these are and if they should be kept around?

 

Also I've noticed in my sand bed I have two spaghetti worms that build gravel tubes and filter feed. They are small for now but are they worth keeping? 

[jservedio]

They are collonista snails and are very common in new tanks with live rock. The only downside is they can get inside your pumps and other equipment, but they are super beneficial.

 

Lots of fish like to eat them too. I had a sixline wrasse who single handedly ate the lot of them in about a week.