I have had mine (( from DD )) for about 2 months now, and while it has a healthy gut, I still haven't actually seen it eat any prepared foods. I am guessing that it gets some that goes behind the rock-work.
It does pick at the rocks all day long, and even a few corals. Minor nipping at SPS -- haven't noticed any damage, just less PE. It does however LOVE open brains. It hasn't touched my zoas or clams yet.
For the first 6 weeks or so I barely saw it, but now it is out and about most of the time, it seems to actually prefer that I have other angels in that tank.
He is in most of this video,
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