Cobweb like spongey thing? Should I get rid of it?

[Seabiscuit & Friends]

Anyone have experience with this stuff?

About 3 days ago I noticed this white cobweb looking stuff growing on one area of a certain rock, since then it has spread to almost 1/3 of the rock. Started out real thin and loose, pretty unnoticeable, but all of a sudden it has started getting thicker and more solid seeming while also creeping along the inner areas of it's host coral. Also has developed little spots that look like worm or polyp holes?

I've been trying to ID it and determine whether it's friendly and won't overtake my whole tank, or if I need to take the whole rock out already.

My first thought was algae but now leaning closer to some sort of sponge?? Husband thinks it's a disease and wants it gone, what should we do?

The white coating on parts of these are what I'm looking at:

 

[blaxsun]

It mind of reminds me of that horror movie: "The Stuff".

 

[Seabiscuit & Friends]

Well it has been removed since the area in the first picture has doubled in size in the past couple hours

 

[Seabiscuit & Friends]

Took out that rock yesterday but it looked like some of that white stuff was left floating in the water... now this new rock is growing the stuff too!! Should I be worried??

 

[madmarks]

It looks like what people call 'a fast growing sponge'. There is a previous forum article on a similar situation to yours. Unfortunately, the resolution was to scrape it off while sucking it up with a vacuum.

There are also other articles on this if you do a Google search for 'fast growing white sponge'.

Here is the link:

White fungus/sponge please help!!!

Hi reefers, I have had this white sponge looking thing growing in a shaded area of my tank now it's spreading and kinda looks like a sponge but maybe it could be a fungus how should it be dealt with.

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