Hello, My clown started developing white edges on its tail fin 2 weeks ago. I cant tell if this is a disease or if clowns develop new patterns. I only have the clown and two turbo snails in a 30 gallon tank. All my parameters are where they need to be and I do weekly 15% water changes. Ive had this clown for just over a year now. See attached photos to see what it looks like! Any insight or advice is welcome, thanks!