There's a fungus amongus

[One_Divided]

Well maybe not among all of us, but among my true perc.. I just got a pair of percs on credit (yay xenia!) at a lfs and I noticed the next days that the female has a small amount of fluffy white fungus type stuff on one of it's fins.. I've done a bit of reading on it but I wanted to hear what any of you might have to say about it? The growth hasn't gotten any worse, but I hear it can end up being fatal.. The fish is eating like a pig.. I'm soaking the food in selcon.. I'd like to avoid doing a quarentine thing.. Or should I just return the fish to the store?