Generally, fish will have split fins if they were roughly handled when they were captured, either initially or at the pet store, or if they have been "roughed up" by another fish in the tank. Minor fin splits can be treated with care in your own home, though it is likely that there will always be a small notch in the fin where the split occurred. However, major tears can only be remedied by an experienced fish surgeon and must be addressed expediently if you want your fish's fins to heal with as little scarring as possible.
Things You'll Need
- Antibacterial solution
- Isolation tank
- Povidone iodine
- Cotton swabs
Isolate the fish immediately. This will prevent the other fish from attacking the fish again and exacerbating the problem. In addition, it will limit the likelihood of secondary infections.
Treat the water in the isolation tank with an antibacterial solution. You should get the solution from a veterinarian or a fish specialty store. It will help keep the wound clean and sterile while it heals.
Check the fin to determine the extent of the damage. If the fin is torn, but the body of the fish is not injured and the thick part of the fin toward the base is not affected by the tear, then any split or notch will be cosmetic and the fin does not need to be stitched up. However, if the base of the fin is affected by the split, then you may need to find a fish surgeon to stitch up the fin and prevent further muscle damage.
Apply povidone iodine to the fin split. The type of fish that you have will determine how you accomplish this. With most fish, you can gently force them to the surface of the water using a net, then apply the solution. However, if you have an elaborate fish like a lion fish, you may need to forgo this step or work with an exotic fish expert to learn how to access the damaged fin without causing further injury in the process.