could be diet, stress, both, or could be happy changes. Does it have enough places to hide, and food to eat, as wrasses eat all day. They swim around eating. sometimes when they become "bored" with their surroundings, they will try to jump. You can notice this behavior when they start swimming in circles or trying to jump up the water coloumn and out of the tank. Lost one once that way, it sucked. Good luck.