yup fairys flashers possums should be good , if you want a wrasse that sleeps in sand ypu cant try tupperware with sand but im not a fan since it will get splashed out and if u cant hide it looks kinda goofy
I did own a Melanarus and red coris wrasse in a bare bottom awhile ago. They just slept on the bottom of tank. Fish store aquariums don't have sand also and they just sleep on bottom of tank.