raised bump

One of my daughters glow fish has what appears to be a small raised bump on its bottom fin. It’s 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. It’s kinda hard to tell since I can’t get a good...

Yesterday I bought two Platys from Pets at Home, and less than 24 hours later I’ve noticed this tiny, slightly raised bump below the mouth of one of them. I’ve attached a photo that shows it quite clearly. Please can anyone advise me on what this might be? I’ve already rang up Pets at Home and...