i had a china wrasse do that in QT awhile back. when i'd take the top off for a water change she'd sit there spitting water at me lol, guess she didn't like me.. :(
i never really figured out what the deal was. does your multibar eat? that was my issue with the china wrasse, it just never ate much. i tried all kinds of floating foods to see if it was feeding related, but nothing.. pretty sure it wasn't oxygen related in my case
are you doing TTM? i'll be curious to know if your fish keeps doing it as you move tanks. mine kept doing it in every tank i put her in, it was weird