What Is This?

[Reef Keeper]

I've had numerous people, over the years, ask me "What is that?," and I've replied "I think it's an ecrusting sponge, of some sort, growing on my live rock...."

Does anyone, here, know what this is? It has these clear looking nodes or nodules on it; similiar to an Orange Tree Sponge, but its shape is not at all tree like, and is growing on three other pieces of live rock.

I've noticed Elite's Avatar has a somewhat similar photo (Not sure what that is either....)

Here are some photos

Thanks for taking peek and for letting me know.... :glasses:

 

[Elite]

my avatar is close up shot of a fungia (http://www.saltwaterfish.com/site_11_03/product_info.php?products_id=513&parent_category=4&category_search=62&root_parent_id=4).

Yours looks like a yellow sponge.

 

[Reef Keeper]

my avatar is close up shot of a fungia (http://www.saltwaterfish.com/site_11_03/product_info.php?products_id=513&parent_category=4&category_search=62&root_parent_id=4).

Yours looks like a yellow sponge.

Thank you Phong. Looks like that clears up both mysteries. H)