Help please my Parrot Fish’s gill is in bad shape!

Please help! Does anyone know what’s wrong with my Parrot Fish’s Gill? It’s been going on for awhile but I thought it was normal until the gill edge blistered and opened up to little tentacles. I’ve been treating the tank with Melafix for about a week. I can’t see any great difference. I do have another week of treatment. I wanted to reach out to see if anyone has delt with someone like this.
The third pic is the left fin that’s starting to look transparent in the middle. Otherwise his behavior is just like the other one that appears healthy.
Thank you for any advice you have!

Do you have the tank parameters?

Ammonia, nitrite and nitrate?

In the mean time, do a 75 percent water change and dose the new water with rock salt (otherwise known as aquarium salt). Stop using the melafix