two nights ago I preformed about a 20% water change on his tank , and the next morning he was very skittish and wouldn't even come to the front glass to see me and would dart away when I opened the lid. I noticed he has a black line on his face that hasn't seemed to heal up for a few days. also his gill plate looks a bit lumpy and weird on both sides ( the only way I can explain what it looks like is when you see those burrowed squiggly lines out of logs and sticks) can someone please tell what could be wrong?
