How was it captured for export?
My understanding is that how it is caught makes a big difference on how long it may survive.
Some fish are net caught, which is the best way. The other way is with cyanide, which stuns the fish. The cyanide can produce adverse side effects to the fish for a month or two, causing it to die.
Not saying this was the issue. but a lil research may help you determine if this is why it died.
To me, it is important to support a LFS that only sells net caught fish, or at least advises you, so you can make a choice. They are a little more money, but the right thing to do, in my opinion.
http://www.fishchannel.com/fish-excl...rium-fish.aspx