Yesterday I was looking for my clown loaches and I noticed that one of my clown loaches is all red around the gills (redder than my other ones) and he has some red spots on him that looks like burst blood vessels. He is also not eating and getting thin, but he is not losing his color. He's not swimming around much, just laying on the bottom in the same place. Does anyone have any idea what could be wrong with him? Any comments are appreciated! Thanks!