Hi Mr. Andersen,
I have kept a goldflake in my tank pretty consistently for the past 10 years. At one point I actually had a pair of the. I have found them to be great tank companions. I love tiny fish, and tiny angels. The goldflake is almost always the biggest fish in my tank.
Thanks to my Fiancee' on the last go around the largest fish was an Achilles. And we were both devestated to lose the Achilles in the crash. I just found her a new Achilles on Weds. And it's a beauty but it's really large.
Now that I have rambled, back to the Goldflakes, at any size they just take care of themselves. They don't go after my other fish (big or small) an they don't go after my dwarf angels.
At the moment, the newest Goldflake is just about 3" and the lips have turned blue - Very important, as this is how the Fiancee' identifies the Goldflake to friends, as 'Blue lips'. But I have softies, LPS, SPS and clams in the tank and have no issues. In the past there has been occassional polyp nipping of SPS, but never damaging or decimating. Just a pick on one coral on one polyps and then move on about their business.
I have also kept Goldflakes with larger angels; Chrysurus, Imperator, Asfur, Koran, Cortez and never had an issue.
In my experience they have been a great fish for my reef tank, and I have no hesitation (other than cost) in adding them to my reef tanks.
Dave B