cottonmouth

I recently out in 3 rainbow fish and then three more a week later. After a few days I noticed their lips were white so I’m wondering if this is cottonmouth and I need to medicate the tank? No other fish seem to have it, and I’m wondering if I have mostly males and they’re just fighting...

I hope this message finds you well. I'm currently facing some challenges with my aquarium, and I was hoping to get some advice. After a recent 5-day treatment with Jungle Fungus Clear and Kanaplex for suspected columnaris in my tank, I've noticed that one of my Neon Tetras is exhibiting...