Borbonius anthias rapid tail movement

[DNACollector]

I just got a new borbonius anthias. I noticed its rapid tail movement since I got it. Currently, it is in a qt tank with UV sanitizer and the tank is covered from light. Does anyone know what could cause this abnormal behavior? Thanks in advance!

 

[Jay Hemdal]

I just got a new borbonius anthias. I noticed its rapid tail movement since I got it. Currently, it is in a qt tank with UV sanitizer and the tank is covered from light. Does anyone know what could cause this abnormal behavior? Thanks in advance!

This species commonly suffers from swim bladder overinflation after collection. Because it is positively buoyant, it needs to constantly swim downward with its tail to maintain position. Being in a bare tank can make the issue worse. Can you supply it with PVC caves or anything? It may not use them (they seem to prefer hanging on the tank walls) but if it does, it will help.