Some things to consider for mysterious deaths
http://www.fishchannel.com/fish-heal...h-that-ph.aspx
Here is a case where someone was unable to keep flame angels after trying many including established ones. Looking at the list of equipment, I do not see an aerator like a skimmer. In my experience, I also had several healthy established angels (in separate incidents) die overnight when I turned off my skimmer (everything else was fine).
http://www.aquariumpros.ca/forums/sh...ad.php?t=30777
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