my 5 1/2 year old veiltail betta, Gill, has been really inactive lately. he will swim frantically with his mouth out of the water for a bit, then settle down, but if he is at the top of the tank, he lays straight up! he looks like he is dead. then if you tap the tank, he does the same thing. he doesnt eat, and he doesnt just cruse around normally, he just stops and goes straight up... im worried, but he has been like this for a week! what going on??:-(