tail rot has spread

[fishmom]

Apollo's tail rot has spread to his lower fin. Need more advice.
I am treating him with Aquarium salt and melafix. What more can I do? He has had this for two to three weeks. Thanks for the help!!!

 

[Kiarra]

Are you changing his water every day?

Honestly, I don't use Melafix for anything. For cases of finrot, I use Blackwater Extract, aquarium salt, and clean water. It usually takes care of it pretty quick.