Growth on Rock

[hannernanner]

Hi R2R! Apologies for the photo quality...I should hit the photography forum next..but I have this brown growth in a few spots on my rock in my new tank (Real Reef Rock, so it wasn't "live" rock) It's encrusting in small patches, doesn't appear particularly fuzzy but does have some texture. Any ideas?

 

[jsker]

Looks like a sponge. What do you think @KJ

 

[sfin52]

I also thank sponge

 

[hannernanner]

Cool, thanks! That's a good one, right?