White growth on coral

[Johng723]

I was away for a few days and came home to see some white growth on a random (not sure what type) coral I had gotten a while back. Any ideas?

 

[Ben.QLD2]

Pineapple sponge
(Sycon sp.)

Growing on a star polyp colony by the looks of it.

 

[Johng723]

Thanks! That’s kind of what I was thinking, but wasn’t sure.
Also, looks a bit different at the base from my GSP, so I wasn’t sure if it was also a star polyp, but you’re probably right.