I just built a DIY python, and I've been planning it for a couple days so I've decided to put off my water change until then. So I was emptying the tank, and I noticed that one of my cherry barbs, A female was swollen on one side. There was a large red sore. What do you gys think it could be ? Im hoping the water change will help. I think I'll do another when I get up tomorrow. The water has a lot of particles in it after the change, which I think is due partially to a new sponge I just put in the filter. There were particles before but not as numerous.