What’s wrong with my bubble coral

[Dlionsfan09]

My bubble coral has been in my tank for 6 months now. Has been doing great. Last night during the middle of the night during wind down time, that part of the skeleton was de-colored. What’s going on with he coral?

 

[Jaylivi1212]

What are your water parameters?

 

[Dlionsfan09]

Alk 9
Cal 450
Mag 1400
Salt 1.025

 

[Vincent100]

I wouldn't worry about it , mine does it all the time than goes back to normal
Any pics of it now ?
Here's mine ,it's been through alot ....
Things have fallen on it , it's been bleached by my new lights but is on it's way back bigger than ever

 

[Vincent100]

There you go the same lol
Nearly every night just after lights out is does this than opens back up with feeders out
I'll get another pic in a bit once it opens again