The fish thats left is acting really wierd, it just sits at the bottom of the tank most of the day, it scootles about when i come to feed it, it eats food and then spits it back out. What am i doing wrong? I feed it 2-3 times a day like the food says, it gets cleaned out regularly, once a week atm as the water goes murky really quick, i dont know what im doing worng