I had 2 pea puffers in my tank when the heater broke. I did not realize until the first one had died. The second one was upside down and spazing out when I poured hot water into the tank. I got a new heater and he seemed better, but not all the way. He is moving around less gracefully than before, and also not eating. Sometimes he would try to eat, but miss the food (frozen bloodworms) multiple times and give up. I have never noticed either one so clumsy before, and I also saw him do what look like a cat throwing up a few times. This happened about a week ago and I have not seen him eat since. Is he a dead fish swimming?