How to introduce an Achilles

[dh350twin]

I want to add my last tang to my tank and that will be an Achilles tang. I have a purple a yellow a blonde naso and a hippo and last and they all get along and have been in there a year, any advice on introducing and Achilles should I buy a larger one or smaller then the other tangs. Fatten him up in the sump or not? Pretty sure the hippo has ich but never flares up on any of them.
Any advise will be appreciated.http://img.tapatalk.com/d/14/08/04/uve5e9e2.jpg

[ca1ore]

There is a very long thread on the Achilles Tang in the Reef Fishes forum - lots of good advice. The AT is a difficult fish to keep and an ich-magnet (maybe even more so than the Hippo). If you are going to try one you MUST quarantine it, both to ensure it doesn't have ich and to get it eating a variety of foods. My experience with multiple individuals over the years is that they are often very picky eaters and take a while to accept most foods. In the competitive environment of a community tank, absent a prior QT, they will often not survive. My approach to QT has been to keep them isolated until they are eating at lest three different kinds of foods. My most recent AT spent 4 months in QT before I deemed it ready for the display (eating spirulina brine, nori, and mega-marine).

I think the most sensible advice would be to not add an AT if you suspect ich exists in your tank. However, I was in a similar place in that my Hippo showed occasional spots (though after I already had the AT in QT), and things have worked out OK. I do have ich in my tank, but so far (almost 10 months ) it has proven controllable. Not entirely sure why, frankly, as in prior cases I had ich wipe out fish populations.