How long will it take for my Betta / Fighting Fish fins to repair?

It all depends, My tiger oscar will fray his fins, then a few days later they will be back to normal. But my sister has three silver dollars who she bought when they were babies. When she got them their fins were frayed, shes had them for more than two years and the fins are still frayed but they are healthy. So it isn't something to be worried too much about.