One of my angel fish (the most beautiful one) has refused to eat for a few days. Everything time I feed the fish, while other fishes all rush to the food to get a bite, he was swimming away as if he was not interested in the food at all. I have not change the food at all and everything seems to be very normal with him. He swims up and down gracefully just as always and there is no abnormal sign shows up on his body. However, he seems to be pretty panicky lately, trying to stay away from any fish, large or small, swiming toward him. By the way, he is in the same tank with 4 other angels and whole bounch of tetres. However, he is the smallest angel I have in the tank (55g).