I would leave her alone, do 50% water change every other day for a week, some aquarium salt, feed every other day opposite water changes. She has know competition for food so she can pick and choose when she wants to eat, then the uneaten food can spoil the water. As Fronts mature they don't require as much food, if she was holding eggs she would go a month without eating. My Fronts eat NLS Thera A as a staple every other day with a treat of krill or brine shrimp on water change day. I currently have two males separated from the colony and they feed totally different as the colony attacks the food and the singles are more lazy about it. Get her some Front friends and you will see her perk right up. I haven't seen anything to make me think she is sick. Good luck.