Mysterious One Spot Foxface Death

[avgreen]

Hey guys, so last weekend I went away for a night and when I came back at like 10pm the next day I noticed that my foxface was breathing quickly and swimming underneath the return pump for my sump where he was unaffected by current. I did not have my QT set up at the time and my LFS was already closed so I had to wait till the morning till I could do anything. The next day when I came back he was dead in my sandbed. He didn't look beat up by anything and I placed the corpse in a freshwater bath to see if it was parasites but did not see any. I have had him for over two years and got him from another hobbyist who had him for a while. Just wanted to make sure that it was not something I could have done or if theres something I should be worried about. The pictured attached is him right after he died.

 

[Qasimja]

did you recently add anything new into the tank? new fish new coral etc? any of the other fish acting strange

 

[avgreen]

did you recently add anything new into the tank? new fish new coral etc? any of the other fish acting strange

Like a little over a month ago I added an orange flame torch but have not noticed anyone else acting strange. Also just to note, I did test my water and everything was fine, my nitrates were just a little high but they always have been and have not affected coral growth or any fish.