hydroid confirmation

[pleasants9]

Are these hydroids? how do i get rid of them?

also is that thing on the left a sponge? good?

 

[valgae]

looks like colonial hydroids and a q-tip sponge. not sure how to kill them other than boil the rock.

 

[pleasants9]

decided to boil the rock... better safe than sorry ill take the loss, it was a fairly small rock. howl ong after boiling can i put it backin the tank?