Fin damage

I got my angles from a magoo’s they were kept in pretty small overcrowded tanks. While they were being handled by the employee there finn’s mostly Spooky(the black angel). I know it’s not fin rot because the molly in the back was quarantined for it, and is now fully healed. (thank god) There fins have not gotten any worse and don’t seem to be getting better at least not very fast. I have had them for a month or too. they are currently in a 10 gal, I know the tank is small for them but I am working on a bigger tank. And I really want there fins to get better before I put them in a more larger tank driftwood, a more heavy water flow, ect. I also just really wanted to get them out of the pet store, but I’m stuck on what to do because I have tried researching and I am just constantly sent to fin rot recommendations.