What is this in my tank under a rock?

[dobly_1999]

Two question:
Is there something wrong with this coral?

This is a picture a couple of weeks ago

Also, what on earth is this grown under a rock in my tank?

close-up

:rollface:Two question:

 

[Reef Junkie]

I would inspect that colony for pests. Hard to tell why it's closing up in that one spot.

The bottom two pics is of sponges. Harmless and beneficial.

 

[zorics]

*nod*
could be a nudi...
how long have you had this colony?

 

[dobly_1999]

I purchased it about 1 month ago

 

[surfnvb7]

hard to tell. you may want to do a freshwater lugols dip just for the heck of it.

reefjunkie is right. those 2 white things on the right are harmless filter feeders. i think they are called "pineapple sponges" or something like that.