Please help with clove polyps issues

[Clown7]

I need some help. My tank is reasonably new and I have recently added a green clove polyps frag. Some of the polyps seem ok but most don’t. They have what seems like a blackish cloves, but not extended. Any tips?

 

[Mr. Mojo Rising]

Need a lot more info to help you. How old is the tank? How long have you had the coral? What are the water parameters? What type of lighting and flow do you have? Why is that one rock covered in algae but not the rock behind?