Identification help?

[lumpadelic]

I got this piece of rock covered in hair algae from a LFS, who acquired it from another customer that was tearing down his tank. Once I got it cleaned up and under lights this guy came back and is spreading pretty fast. Any ideas what it is?

 

[Lazydayz]

I'm no expert but kind of looks like a war coral (favites). Looks great!

 

[lumpadelic]

I'm no expert but kind of looks like a war coral (favites). Looks great!

That was my first guess. Thanks for the reassurance!