flame angel deaths

[brownd1]

hello

ii'm new to the hobby (lots of years with f/w)

I've had a small tank for a year & just recently setup a 50 gal reef tank

I had a flame angel for about a month, this fish had bee in the lfs tank for about 2 weeks before I bought it.

for the month that I had this fish it ate great , showed no signs of desease or injury.

This week it stopped feeding & hide in a corner

the next day I found it dead?!?!

I did a web search and found this article

Any comments ?!?!

http://www.amdareef.com/mc_ptsd.htm