Hi all! My betta (Gunter) has had these weird see through areas growing on his fins. They started small but have been growing downwards (second photo from about two weeks ago), and I cant find anything that looks similar online. His water tests all come back perfect (ammonia, nitrite, and nitrate all at 0) and he seems completely normal otherwise. For background, We got him for free since he was basically dead. He was completely grey with bad fin rot but got better with clean water and tannins. Im hoping this isn't a sign of the fin rot coming back! Has anyone here seen anything similar?
https://www.reddit.com/gallery/1pwio6b
Posted by uhoh-its-me