White growth on hammer coral?

[TKBIndy]

Is this some kind of sponge or anything I need to be worried about?

 

[Hitman]

Sure look like sponge although I can’t say what kind. How new is the tank? If it’s a young tank it could just be a sponge growth using up the silica in your salt mix or water if not using rodi which is normal.

 

[Tahoe61]

Yup sponge. Harmless

 

[TKBIndy]

Ok - good news. Seemed like it was growing fast! Tank was set up in April so pretty new. I do use rodi water.