Odd tang behaviour...

[Quinn]

Naesco, why, I didn't expect you to show up on this thread at all!

I have a 150 gal, 48x24x30. It is the only large fish (out of four fish). I think in retrospect I should have realized that this guy was pretty much unsuitable for the tank, considering it's in the Acanthrus genus. I found that what little information was available on the species was conflicting (not much of an excuse). I do plan to remove him when he gets larger (6" or so), but for now, I just want to ensure that he does well in the available conditions. He's eating basically a sheet of garlic-soaked nori a day now. As of this evening he's calmed down a bit, less pacing, but he's hanging out at the back still, whereas up until when he started this odd behaviour, he was out and about all the time. He also has what looks like scratches on his face, likely from banging into rocks all day. I am about to do a water quality test, none of my other livestock looks stressed in any way.