What are these White/gray things?

[GaryDZ]

What is this.

I have several spongy like finger projection extending from several rock that are multiplying.

They are white/gray measure about 3mm wide and 25-30mm long

Thanks in advance.

Gary

 

[RBU1]

Yes sponge not bad.

 

[Recty]

They look like sponge to me and they are not at all a bad thing.

 

[GaryDZ]

Thanks everyone....

I was getting a little concerned because there has been a marked increase in the last month and a few stalks are growing inbetween some coral mushrooms