Black patches on Clownfish

[Riverpig]

Hi everyone,
Our Clown has developed two darker spots under it's scales. They've seemed to have gotten darker over the past days. My boyfriend and I tried to Google the issue. However, we haven't found anything that looks anywhere close to the actual patches. The Clown does feed normally and behaves like a Clown should. :jester:
Is it sick? What causes those patches?


Our tank parameters:
Ammonia: 0.002 mg/l (ppm)
Nitrate: 0.004 mg/l (ppm)
Nitrite: 0.200 mg/l (ppm)
Ph: 8.50
Temperature: 25.1°C
Tank size: 80L
He shares the tank with a Goby and a pistol shrimp.

Thank you very much for your help,

Riverpig

 

[snorvich]

Are there anemones or LPS corals in the tank?

[welcome]

 

[Riverpig]

Thanks for the quick reply,
We've only got soft corals like pulsing xenia and GSP and a small (3 head) Acan Lord LPS, no SPS. We haven't got any anenomes either.