My flower horn has a white circle on the top of his head. I swear it makes me thinks of a newborn with cradle cap. He is eating fine and acting normal. I need advise.
Keep the water clean and add salt. I wouldn't feed as much and I would get some good food with garlic like new life spectrum. Feed that to boost immune system. Try some pimafix/melafix for the scrape/wound and to aid your fishes slime coat. If he had a healthier slimecoat that would not happen as easy. What kind of filter are you running? Do you use dechlorinator on tap water? Keep the water clean just dont overclean your tank he needs the beneficial bacteria for his slime coat.
I keep him in a 125 with a 30 gallon sump. His only tank mate is a 6" Spotted Raphael. I do water changes twice a week and add API Stress Coat + to dechlorinate. I did just switch recently to API. I guess that might be the cause. Already keep temp at 85. Not sure if I should bump up more. I will try adding some aquarium salt when I do the water changes. Thanks for the suggestions. That's why I love this site.