Hello, I just noticed my clownfish has a white, stringy, almost threadlike spot on her one fin and she hasn't been using it. Besides that, she is acting normally, moving around okay, and eating normally. I also have a watchman goby and pistol shrimp in this tank, and both are fine. I haven't added any new rock, CUC, or other fish since I got this clown about 6 months ago. I did have aa giant aiptasia (that won't die no matter how much aiptasiax I give it) that I tried to remove today, so I'm not sure if it's an injury from that or if it's some type of disease. TIA!