Help!! Can you help me identify what is growing on my Live ROck

[MIT_David]

Have some grown on my live rock that I have no idea what it is. Started on one rock, now on two of my live rocks. Can anyone help me identify what it is and if I need/should do anything about it?

Thanks!!

 

[reefiness]

Looks like a sponge

 

[Spartanwarrior]

+1 sponge. all good. help to siphon out excess nutrients. its a sign of a healthy tank!

 

[MIT_David]

Thanks!!

 

[Curly0427]

Can anyone help me identify this growing on my live rock? Not the hair algae but the brown branch like cluster