is it pooing or?

[inspirestudioca]

My brain coral these looks colour more ligher than before but also can eat. Tonight i found this coral shrink his body and open the wide mouth,these black? Stuff coming out ! I just feed him today afternoon, so is pooing or?
Thanks everyone!

 

[P-Dub]

I have never seen that. How long have you had it? How long has it been doing this? Is it or has it reinflated and closed the mouth? Have you made any changes to the tank lighting, flow, chemistry?

 

[DSC reef]

Looks to be expelling zooxanthellae or pooing. It's common but could also be a reaction from a stressor like light shock or chemistry swing. If it returns to normal then I wouldn't worry to much.