Who Gives A Fish Forums

I had the same issue until I switched to auto-feeders. Now they get small portions throughout the day, and the aggression dropped. My tank is 90 gallons, 8 discus, no tankmates. I use LED lights on a timer, 8 hours a day. Substrate is bare bottom for easier cleaning.

If it's bacterial, kanamycin's a gentle option. Avoid heavy meds unless it's a last resort. Discus don't always handle meds well.

I'd lean toward water quality too. Even if params are good, dissolved organics can irritate fins. Try adding some Indian almond leaves—they've got antibacterial properties and might help.