What is this growth?

[icepick5587]

I found this wierd white growth on some liverock in my newly setup nano tank. It came about after 4 days of having the live rock in my new tank. Maybe a sponge or some kind of algae? If anybody knows what this is and whether it is something I should keep or not please let me know.

 

[Amphiprion]

I suspect a sponge, but it is still difficult to tell. Just leave it alone and see what happens. I can tell you now that it is probably not bad, though.

 

[icepick5587]

It's pretty ugly.

 

[Brandon's Reef]

[welcome]
yea I have one in my 54

 

[icepick5587]

Is it still alive?