White growth on rocks

[garyfri]

Thank you in advance for any help and if this is not the right section let me know and I will move it. I have an aquarium that is 2 months old. I moved 1 rock with anemones on it to this tank after a 1-month quarantine from my old 75-gallon tank (2 years old). Only that rock has the white stuff growing. I looked at other threads and this did not look like what was called sponges.

 

[fishguy242]

hi,it looks like sponge to me?

 

[KJ]

Agree^^^

 

[garyfri]

Thank you both.