My 10 year old female clown started exhibiting signs of stress this morning. She was at the surface like she couldn't get enough oxygen and had hair algae ganging from her stomach area. I did a 30% water change then dosed Stress Coat and added carbon to the tank. This is a fish who always eats well yet today she refused food and hid when I tried feeding her. I don't see any visible injuries and she is the only one in the tank. Tank is a 29 gallon well established LPS and softie tank. There is an airstone in the tank and the top is open so I don't think lack of gas exchange is an issue. Right now I'm mixing up some garlic/ fish food in a last ditch effort to try and get her to eat. Is there anything else I can try?