My yellow tang died! Why?

[Gooli]

I am pretty sad over here....my yellow tang "Sunny" died.

I've had this 4" yellow tang for over a year in my 90G reef.
He has been eating well and has been active the entire time.
I woke up this morning and he was swiming in small circles. He still had his vibrant yellow color and no physical signs of illness at all.

My wife just called me and told me he's laying on his side with a crab on him! All my other fish are fine.

What in the hell could have done this to him? the only recent changes in the tank is that the temperture fluctuated from 78 to 82 degrees in the last day or so AND i added a copperband butterfly fish a week ago.
This couldnt be the reason could it?

any feedback would be much appreciated.

 

[White Tiger]

Before your tang died, was it breathing rapidly?

 

[Gooli]

no

 

[White Tiger]

How many fish do you have in the tank that your tang died? How many gallons was the tang in?

 

[Gooli]

90g tank...about 8 fish..all small 2-3"

 

[White Tiger]

???????????????????? My best guess about how your tang died would be the quick changes in temperature in the water. But 82 degrees is still in the safe range for tangs. As a result, I am not sure how your tang died.

Another possibility would perhaps be that there was a rapid shift in water chemistry in your tank, thus causing the tang to be stressed out to the point of death.

 

[BTTRFLYGRL]

Was the Copperband quarantined prior to placing in the main? He could have brought in a disease or parasite..Watch your other fish