Aquarium fish diagnosed with damaged fin usually would not suffer from any life threatening effect and usually the condition would heal by itself and the process can be assisted with some simple treatments. Although fins that are torn can cause the fish to swim in an awkward manner but as long as it can still compete for foods and eat well without showing signs of illness, there is no cause of concern. Adding some salt should be a good remedy and usually the desired salt concentration should be about 0.5%. This will help to prevent infection and at the same time provide a tonic to the fish to assist them so that the wound will heal faster.
Sometimes depending on how bad the condition is on shredded and torn fins, you should not make a hasty judgment and apply medications excessively hoping to get fast results. Most often, it is the overdose use of medication that causes more harm than letting the fish heals by itself. Some of the common remedies suggested like potassium permanganate doesn’t really go to the extent of quickly fixing the situation and I find that most of the time, other things will get even worse because the chemical can actually kill the population of beneficial bacteria that resides in your aquarium filter. Instead of applying the medication, I would suggest that you concentrate on ensuring that the water condition is a good as possible during this period and crystal clear water should be used as a good benchmark on your tank water quality.
Finally before you get everything started, first make sure that you have not mistaken or confuse yourself thinking that ripped fins condition is a fin rot disease which is actually a more severe illness. It can be very easy to differentiate between those two because torn and shredded fins will appear as just having a split while fin rot will have a decaying and slimy looking appearance showing on the overall fin especially at the ends. For more information related to this and to get a better picture, head over to fin rot disease page.