white thing growing on rock

[Nimo]

I thought it was a sponge but now not sure

 

[Fishman007]

Looks like a dead sponge, i have hundreds in my tank, red,white,purple,yellow, so many types. Look anything like this?

 

[Nimo]

Looks like a dead sponge, i have hundreds in my tank, red,white,purple,yellow, so many types. Look anything like this?

Yes there are 2 of them atleast but they seem to be growing not dead.