He's acting strange. He's in a 10g divided tank, but currently the only fish in there. My ammonia is 0ppm, nitrates 0ppm nitrites 0ppm, pH is 8.2. Been using the same water sense September of last year. I was noodling around in his tank earlier, changing some decor and put new marbles in but I washed them thoroughly and my hands were clean. Later, I found him stuck on the intake valve of the filter, so I moved him to another section away from the filter (though it's never given him problems before?) He's laying on the bottom breathing heavily right now, and he isn't all happy dancy when I come see him. Nothing else on him looks amiss. Please help?