What is this on my trumpet coral?

[DTeeVee]

https://imgur.com/a/LYsZR

On the top head there is a black patch. It looks like the stalk from the side but it looks like a dead spot/decaying piece from the front. Anything to worry about?

 

[AlSimmons]

Can you take another picture without the blues on?

 

[DTeeVee]

If I remember I'll get one tomorrow