I got my betta on 9/27 and he had fin rot from the get go. I put him in a 2.5 gallon salt water treatment on 9/30 doing daily 50%water changes there is an air stone in with him. Then last night I did his water change, put him in a halfway solution then back in freshwater. The first picture is from this moring, his caudal fin split and looks like a piece from the middle is gone. There were holes in the fin where it split to. And his dorsal fin shredded. This all happened in 15 hours. I don't know what to do. He seems like he had more energy yesterday, he wouldn't stay still for a picture. The difference between yesterdays water and todays is: no salt, the air stone was a little lower pressure today, there was a filter in the freshwater, i took 1 silk plant out and put a different one, added API Stress coat plus. The first picture and the last 2 are this morning, the 2nd thru the 5th are the last 4 days that he had been in the salt treatment, 10/3, 10/2, 10/1, 9/30. I need help figuring out the next best thing to do with stressing him too much. I don't know what caused the sudden change in his fin condition or if his fin was meant to fall off where the holes were. But his dorsal fin shredding concerns me a lot.