so I had columnaris in some neon tetras before, so I treated the main tank with 1 course of kanaplex and 1 course of furan-2. After that I moved the neons into a quarantine tank and dosed 2 more courses of furan and 1 more course of kanaplex. The neons healed some so I thought they were good. I left them in quarantine for about 2 more weeks then moved them to the main tank again. They were all doing good but 3 got a little worse and had the scabs on them. They all eat and swim normally but they still show signs. I separated the 3 that had the scabs yesterday so I'm sitting here wondering why all that medicine didn't do ****. The neons are the only ones showing symptoms of the disease even after being with the guppies and female beta so Im starting to think its something else. Columnaris is supposed to kill the affected fish in at the most a month but they've been "sick" for about a month and a half and still none have died and they all still eat and are active. Here's a picture of the 3.