White spot on fish

I have a gold Molly and noticed today there is a spot above her fin. No one else in tank has anything. Its been only in tank over a month. I Google but can't find a similar picture. Please provide any suggestions of what it might be. Thank you.

Looks kinda like a bacterial infection. If you can, get her separated from the others, preferably in a 5+ gal quarantine tank with a heater+filter. You don't want the others to get it.

I'd make a run to your local pet store and pick up something that is aimed at bacteria infection. Often times you will find "all in one" treatments that target fungal and bacterial infection, something like Tetra fungus cure might do the trick. Also, add some aquarium salt to her water too, molly actually prefer some salt in their water and it should also help kill off some of the bacteria.