My clown fih has a growth.

[jimbau]

One of my two clown fish that I have had for approximately 5 years has a growth on his chin. He seems to be spending more time laying on his coral and although he is eating it is not with gusto or as much. Anyone have any ideas what this is and how it might be treated?
Water parameters;
Nitrate 7ppm
Phosphate 0.006
Calcium 450
Alk 8.0
PH 7.8
Mag 1250

I have not added any fish for over six months and have quarantined everything.
Here are photos and a short video. The growth is on/under his chin.

 

[Humblefish]

Looks like Lympho: https://www.reef2reef.com/threads/lymphocystis.257461/

 

[jimbau]

Thank you Humble Fish seems to be what it is.

 

[melypr1985]

agreed with lympho. It's a pretty weird one.