What's going on with this pipe organ?

[Morpheosz]

I've had 2 pipe organ varieties next to each other for about a year and they have grown like crazy. Recently, one of them stopped / greatly reduced its polyp extension and now I notice what looks like other polyps growing between the polyps. I'm curious if this is some invader or phase it's going through? If the former, should I remove the coral so it doesn't spread to my other pipe organ? They just look like little purple polyps and seem to be slowly covering the skeleton. As always, hard to get a great pic, but the bright light blue polyps are what remain of the original coral polyps, the dark purple is what seems to be new.

 

[FernFish]

Blue clove polyps ?

 

[Morpheosz]

Blue clove polyps ?

Great suggestion, but looking at pics online they seem to have a very snowflake-like appearance which these seem to lack. These polyps also look smaller, with 8 pretty smooth "appendages".

 

[Science/G]

Pipe organ has long skinny red coralites the the polyp comes out of

 

[Morpheosz]

Pipe organ has long skinny red coralites the the polyp comes out of

That’s what is beneath the bright bluish white polyps. This is just a top view so you can’t really see the base structure.

 

[Science/G]

That’s what is beneath the bright bluish white polyps. This is just a top view so you can’t really see the base structure.

It is a true pipe organ coral. Don't know why it's unhappy. Any changes in water parameters?

 

[Morpheosz]

It is a true pipe organ coral. Don't know why it's unhappy. Any changes in water parameters?

I'm pretty sure it's whatever those dark purple polyps are that I pointed out that are slowly taking over, that's what I'm looking to get identified.