White Coralline?

[Tigershark22]

I know the image quality isn’t great. I can take better pics if need be. But does anyone have a clue what this is? I’ve noticed a white growth in my reef tank. This area initially had a sizable patch of a beige looking algae upon setting up the tank but I watched it fade away and appeared to be just the typical greenish algae on live rock. I’ve recently noticed a large patch of white. It has interesting texture. Almost studded like a golf ball. I would have assumed it to be dead coralline from online searches but it is much thicker in appearance than the original algae and genuinely appears to be growing.

 

[fishguy242]

looks like sponge

 

[Tigershark22]

looks like sponge

Okay that’s interesting, didn’t think about that possibility, I guess it just looks so rigid.

 

[Tigershark22]

looks like sponge

Okay that’s interesting, didn’t think about that possibility, I guess it just looks so rigid.

 

[Sawacoral]

When it doubt, poke it. If it gives way easily it's prob a sponge.

 

[rhitee93]

Sponge was my first thought too.