A few days ago my betta stopped eating and spent all his time at the bottom of the tank, just lying there. He is in a divided tank with another betta - I've had this setup for about 9 months. I don't think it's water quality or temperature or anything like that because the other betta is fine and still eating and swimming. I've been feeding them bio-gold pellets but I tried some blood worms just to get him to eat but he won't. And now, several days later, he is laying on his side, only occasionally going to the top and then just falling back down. He doesn't have any spots or anything on his body, no signs of any kind of infection. Is there anything I can do? Please help him!