One of my daughters glow fish has what appears to be a small raised bump on its bottom fin. Itās the same color as the fish. It seems to be eating normally and the last water change was almost a month ago. The other two fish do not have a bump. Itās kinda hard to tell since I canāt get a good picture but Iāll take any advice. I took several pics with bedroom lights on and off in case it makes a difference. Thank you!