This hole suddenly appeared on my half moon's back fin today that wasn't there yesterday. Is this normal? What could it be?
There have a couple of splits at the end appearing for a few weeks now but I thought that it was just growing. Now I'm starting to think that there's something wrong since there's a hole near the split from earlier. I don't think there's anything sharp in my 2.5gal tank, but there are a couple of ghost shrimp. I also do a water change and test every two days so I don't think it's fin rot. Any input is appreciated!