I recently got a twin spot wrasse, about a week ago, and could not find them last night. Couple hours before bedtime. search the tank throughly and for sure that something happened to my new fish but what did it jump behind the tank? I saw a thread saying that their butt likes to bury itself in the sand before bedtime and made me feel a bit better when I woke up really early still no sign but then around the time I get up about, 45 minutes after I turn the lights on, the wrasse was there . I hope this post helps somebody who is wondering where their wrasse is.