I have had my betta fish for about 9 months now and the last few days, I have seen that he is not eating when I feed him. He will swim up and put the pellets in his mouth and then move his head a little bit then go after another pellet. The problem is that he then lets both pellets back out of this mouth. He will do this a few times until he just swims away. He was eating fine until monday morning after a weekend fast. He usually gets fed in the morning. Last night though, I gave him three pellets and he finally ate. But then this morning, he would not eat again. I have just introduced a new filter into his tank last wedneday. I hope someone can help me!!!