It should be fine but keep an eye on him to make sure it doesn't get worse... do you have any nippers in your tank? I was really surprised to find out that my neon tetras were responsible for taking a nick out of one of my male guppies - they look so tiny and unassuming but underneath it all there's pirhana blood coursing through their veins.... !
It doens't sound to bad anyway fins heal naturally. Like you were told before if you have any fin - nippers you should remove them. I prefer to use the natural healing so don't buy any medication becasue it isn't bad. There are bad cases where medication is needed.