Filefish Swimming Sideways

[wicked_chicken]

I recently purchased a Bristletail Filefish for my SW aquarium. He seemed to be doing fine after adding him to the tank (yesterday), but today he has been behaving strangely, hiding near my filter intake sideways. I fed the tank a frozen food cocktail (shrimp, etc), and he ate, but now as I've said, he's swimming sideways. So far as I know, this isn't normal.

Anyone help? My water parameters seem fine, and the only other inhabitants (Flame Hawkfish and False Perc + Rose Bulb Anenome) are all thriving.

 

[kdpuffer]

My buddy had a matted filefish that always hid in the top corner in weird positions. They are nocturnal so take a look in the tank an hour or so after lights out and he will likely be cruising. The fact that he ate is a good sign he is healthy.