What the...?

[SueAbu]

This growth is at the bottom of my Kenya tree. When I first got it, a few months ago, it was just 1 little opaque finger that I kinda thought was some stray glue. I recently moved it and turned it around to find it had made friends. These "branches" are pliable and wave in the current, but don't seem to have polyps.

Am I good? Or in trouble??
Thanks!

 

[Saltyreef]

Sponge. Can be invasive. Just remove with your fingers or expose to air for a minute or so.

 

[SueAbu]

Sponge. Can be invasive. Just remove with your fingers or expose to air for a minute or so.

Thank you!! He's much better today... Although he was piiiiiissssssssed yesterday. Wasn't sure he'd come back... Especially so fast. I did lose one piece of the invader, somewhere, so I haven't seen the last of it, I'm sure. Now I'm know what to look for....