Hey, I have a ten gallon tank with two pepper corries, a rainbow shark (I'm working on an upgrade) and a bleeding heart, black widow, and rosy tetra. My tank has been running for about a month, and I added the corries a few days ago. I have 1 little guy that isn't as active, and his colors are faded, unlike the other one. I separated him since I was worried he might be sick... HELP! I waited a few hours and just put him back in my big tank because his water got cold. He was looking better but he was shaking his tail a lot and following the other Cory around. Is this possibly mating? I waited a few hours and added some stress coat (since it looked like he got nipped a bit) and now he regained almost all his color and is swimming around normally! What's going on?