The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
As per most hard to keep species; the archilles IMO is one of the hardest tangs to keep. Her in Aus they come at around $250 minimum, but the LFS's continue to stock 5-6 a week and you see every buy them, the one or two that remain get sick, fin rot; ich etc..and they just go downhill.. I'd stick away; although a very beautiful fish.
I've had my achillies for many years now and the only problem I had with it was ich back when I first got it.
After copper treatment, I've never had a problem since.