Macros and Star Polyps

I've got a rock covered in Bali Green Star Polyps.  It was very thickly covered a month ago.  At that time I placed a piece of "brown grape calerpa" (what it actually is, I don't know... it's brownish/yellow but looks like grape calerpa)  near the rock.  The macro tripled in size seriously encroaching on the star polyp rock.  I removed the macro from that area a couple days ago after noticing a decline in the star polyp "fullness".  Now the rock looks like it's in serious need of "Rogaine for star polyps"... it's very thin between polyps.  I'm sure it will recover ok, but just wondering if thats happened to anyone else and whether it was due to reduced lighting from all the macro overgrowth or an interaction between the macro and coral?

I have some brown sea mat that has been slow to open lately.  I wonder if the change in temperature has affected anything.  My tank has risen a couple degrees warmer in the last couple weeks.

I also have taken out, then added again different macros in my refugia.  Maybe that was affecting them.  I didn't worry about it too much.  I just figured that was part of nature.

My tank is running hotter then normal too, but I don't think that's it.  I've got two patches of this and the other is fine.  Here's pics.

This is the piece that was overcome by the macro algae (it's looked like this for about 3 days):

 

Here's another patch of the same stuff on the other side of the tank: