My little comet goldie is acting strangely. Its hard to describe but i fed them a little bit and they ate all of it so i fed them a little bit more but this time he just hung out at the top but appeared to struggle swimming. He really had to put his back into it (literally). Now looking at him he seems to be acting normal again (swimming around the bottom and poking at the gravel). I'm not sure if its just me being paranoid but his body looks a little deformed. Hes got a big head and then his body is just skinny. i've had him for about 2 months now so hes not a new fish. He is a rescued feeder and is only about 1.5 inches long. I know that feeders can sometimes have defects but hes really nice looking and i would hope for him to survive, even if he is a bit deformed. Hes in a 40g. tub with an aqua tech 30-40 pump (i think) with 3 other 1.5inch comet goldfish. I got them so they could go in the pond in the summer so its not a permanent home. ph -7.3, trites-0, trates-5, amm-0. all the other fish are fine and now he appears to be okay to. Maybe it was just that one time he was acting strangely. Any ideas? He looks completely fine, no fungus or any visible abnormalities.