Identification. ..

[ryan.helmbright]

I just upgraded from a 75 to a 180gal..this rock used to sit under many others and was virtually hidden. Now it's in the open and I've noticed a growth on it over the last week. It's white and has a soft, silk, leathery look to it. .

Any help in identifying this would be greatly appreciated!
https://uploads.tapatalk-cdn.com/20151221/78f6fcf95937bfc2b40cdd16fa703986.jpg

[C.Eymann]

Sponge

[Michael Hoaster]

sponge

[gmpolan]

Yep, def looks like a sponge. Harmless and good for the tank