Fish Death

[Greguls]

So I just bought a yellow tang last night, I drip acclimated it for an hour and some change, the fish went in and was a little shy but other than that went right to grazing on the rock, I turned the lights out and then later when I headed to bed I noticed that he had tucked up under one of my rocks and seemed to just be lying there almost on his side, his fins were moving slightly and his breathing didn't seem to be stressed but I checked my water anyway. My parameters that I currently test for seem to be fine:

Salinity=1.023
PH=between 8.2-8.4
Ammonia looks to be only slightly higher than 0 but less than 0.25 ppm which I assume is not toxic.
Nitrite=0
Nitrate=0

I use the API Saltwater master test kit and all my reagents are still fresh (not expired). When I set the tank up I watched a huge Ammonia spike and as it fell I saw a pretty significant Nitrite spike and it fell all followed by a pretty significant Nitrate spike which i rectified by a couple of water changes and adding some macro in my sump. All indications seem as if the cycle happened just fine, so I am unsure what is causing the fish death. I have a black ocellaris clown, who does not have any indications externally of any sort of disease at all, he eats fine and swims fine with plenty of energy, and I also have a Condy Anemone who is not only living but seems to be thriving in the aquarium. I don't feel like its my water quality that is suffering but then again I also can't figure out what caused the seemingly healthy Yellow Tang to do what he did. When I woke up in the morning with my lights on I saw him in a different spot than he was the night before, and I could see him wiggling around, but before I got home from work he had died. Any ideas would be appreciated. Thanks in advance.

 

[Marshall O]

This likely wasn't the cause of death, but a one hour drip acclimation from a fish bought locally is excessive IMO. Next time just float the bag to temp and do more like a 15 minute drip acclimation. Again, I don't think that was the issue, just pointing it out. It is possible you bought a sick fish (even though it may not have shown any visible signs). How did it look in the store (i.e. did you witness it eating)?

 

[Greguls]

I witnessed it grazing, and it seemed to be swimming just fine in the store, the color was good, no stripe or anything, its a mystery because it lasted like 4ish hours before it started acting stressed, and before that it was crusing around, shy but seemingly happy and grazing at my algae. I can't imagine my anemone would make it through poor water quality but the Tang couldn't. I am really hoping that the fish was just sick and that is what happened, I am going to talk to the store I bought it from tomorrow with a water sample so I can see what he thinks about the water...I am at a loss.

 

[mike007]

Most reputable fish stores have a 24 hour guarantee. The fish was either stressed out or sick before you got it. That's another reason to quarantine newly bought fish.