Clownfish discoloration

[10galtank]

Good evening, all

I have had this clownfish for around a month, give or take. However, as of today, I noticed his color starting to look splotchy. He was always a monotone orange, never the brightest but never dull either. He has been lethargic, always sort of has been, but more so recently. I thought it was because of my damsel, so I removed it after watching it be too aggressive. Now, he will swim to the front of the display, look around, and return to his lifeless corner. Can somebody please help me identify the problem?

I do not own a QT tank, is there anything I can do in the display for him?
I currently house a cleaner shrimp, green Duncan coral, and two tomatoe clownfish.

 

[blaxsun]

Is that an injury above the eye?

 

[j.falk]

Is that freshwater gravel?

 

[10galtank]

Is that an injury above the eye?

No, it is not.

 

[10galtank]

Is that freshwater gravel?

Yes, real rock. No plastics to leech into water.

 

[j.falk]

Yes, real rock. No plastics to leech into water.

There is a big difference between freshwater rocks and saltwater sand/crushed coral...

 

[10galtank]

There is a big difference between freshwater rocks and saltwater sand/crushed coral...

Yes, I understand. However, I feel as if my tank decor is not the problem to my clownfish…

 

[10galtank]

There is a big difference between freshwater rocks and saltwater sand/crushed coral...

I have 10lb of live sand under a thin sprinkling of rock. If I really wanted to, I can run a barebottom tank— I don’t think this decision is discoloring my fish.