Is my fish sick???

[lines_michael]

I apologize for my lack of knowledge. I have a saltwater tank and a little blue fish in it. It looks like a blue damsel.

Before: All bright blue

Now: Blue but has a brownish color almost all over him. Still eats fine, swims fine, all other fish seem ok.

I have been moving rocks and lights a lot lately and also accidently put in 5% of my tank volume with 65 degree water during a water change. I thought it was at 78 degrees like the tank. The tempurature dropped a few degree's pretty quick and then came back up fairly soon after.

All levels are ok with just a little bit of nitrates in the water. Didn't measure phosphates (should I?).

What the heck is wrong with my fish and what do I do?

 

[waterfaller1]

What kind of damsel, some do change color as they mature.

 

[Hattie B]

Also some change color with stress.

If there was a rapid shift in temperature he could be showing signs of stress.

My Fox Face turns differnt colors at night (sleeping) to almost all white/brown with little yellow, or when he is hiding.

 

[lines_michael]

if it is stress, which I think it may be. Is there anything that I can do to help??

 

[waterfaller1]

If it's another fish bothering it, one of them may need to go. What size tank? Are any of your parameters off or fluctuating? Yes ,you should test for PO4.