dragon wrasse

I just got in a dragon wrasse today, juvenile very small. After acclimating he was doing fine at first but now he's sticking to the top of the tank occasionally trying to swim down only to come back up. I considered this maybe swim bladder issues but I'm not sure the best way to deal with this...

I have had a Dragon Wrasse (also known as Hawaiian Rock Mover Fish) for close to 4 years in a 340 gallon mixed reef aquarium. The fish is beautiful, has a great personality, and is healthy. Agressive frozen food eater. He's a mixed bag of feelings for me to get rid of. He's cost me hundreds...

Do Dragon Wrasse absolutely need sand? Or can it live without sand?