gota stress, theres no quick solution here. melafix or worst still
copper based medication can slow or stop the condition. Although as stated in another thread. first find the cause, then treat the symptom, then hope like hell it heals over without incident. It can take a couple weeks to notice anything, could take months, maybe not at all, just 2 fish cruising called the pit brothers. This sort of thing is case by case. Just ensure your parameters dont slip, feed them the right food, check the conductivity issues, treat wisely & dont forget your sence of humor cause you could be waiting longer than vassilli to hit the mark.
just a tip in case you missed it, pond strength melafix is more ecconomical for the $. @ least here it is! just need to watch the dosing.