Hairy Mushroom Coral Splitting?

[osprey440]

I have seen this coral do this before but it didn't split. I am wondering exactly why these corals do this.

 

[reefkprz]

generally it means its ingesting its slime coat which it uses to catch bacteria and planktons.. aka its eating.

 

[coralreefertom]

Mushrooms divide through a number of ways. They can split in two , and even leave a piece of itself behind to begin a new solitary mushroom.
Mushrooms will also grow and shrink from time to time as well as cloe up due to feeding responses or as a means of protection.