>I can guarantee u the Mr hiller does not have that fish in his tank<
I can guarantee you that he does.
And has had the fish for about 4 years now (just checked my notes), and the fish has eaten nothing other than Acropora, Pocillipora, and Hydnophora. Does not touch LPS, or Montipora. Won't take any prepared or frozen or live foods. It was originally in my 110 for about a year or so before I shut that tank down and moved everything into my 400 G. Dozens of people have seen this fish in my tank, so please let's not say it is a figment of my imagination.
How does false info like this get spread around? I've also tried adding a second fish to mate up with the first. My understanding is that Joe Y. at Atlantis has successfully done this in the Atlantis reef tank.
I got a hold of a second filefish and had him in my frag tank and he/she? fattened up. Once it was healthy I introduced it into the 400 G with the resident filefish. Unfortunately, they did not seem to get along as the new filefish went into hiding and was never seen again.
I'm surprised of the mentions above of people adding one to a large tank and having so many problems. My fish seems to spread any damage around to all the colonies, and other than keep the polyps retracted, doesn't really cause any damage. My pair of golden angels cause a lot more damage, eating tissue at the base of some Acro colonies (and NO it's not the AEFW flatworms).
There are some shots of my 400 gallon in this thread, but they are a bit dated, there's been a lot of growth from that time.
http://www.bostonreefers.org/totm/2006Fall/
The front page of my old web page has some photos of the fish. (greghiller.com) There was someone at my place just a few weeks ago that made a little video of the tank, and as I recall by turning out some of the lights at the end of the shoot we were able to get the fish to do the standard 'perch' that they when they are getting ready to sleep. Mine sleeps in it's choice of staghorn Acroa. I believe they got this all on film.
FWIW, if you ever dive in the Indo-Pacific you know that this fish is extremely common, there's one hovering over just about every Acropora you will see. Someone in my club recently compared them to hummingbirds....good analogy.
Let me state my position again on this fish....if you have 100 gallon or larger system with a lot of Acros or Pocillipora, and don't mind having the polyps retracted, go for it. Don't expect the fish to take any prepared food of any kind. Also, you will need to get the fish quickly from a shop (or mailorder) as they are not likely to feed it Acros for you.
They are still available in the hobby. I saw one at a shop just a week ago.