White stuff on live rock

[Garygriffey]

I am new to this whole saltwater thing and trying to find out what is on a couple pieces of live rock that I have. I was told the one in the first and third picture is a sponge and the second one they are not positive of

 

[Billdogg]

the little curlycue things in the top picture are spirobid worms. Generally harmless but can reproduce quickly. I find that they grow best in the sump and other low light areas. I leave them be.

 

[Garygriffey]

the little curlycue things in the to picture are spirobid worms. Generally harmless but can reproduce quickly. I find that they grow best in the sump and other low light areas. I leave them be.

 

[Billdogg]

I'm pretty sure thats some sort of sponge.

 

[Garygriffey]

I'm pretty sure thats some sort of sponge.

Ok so my next question is, is it safe for corals when I get to that stage