Just as the name suggests, fin rot is when the fins of fish start to rot away. One of three types of bacteria can be responsible for fin rot – Pseudomonas, Aeromonas, or Vibrio. This is most common in aquarium fish and is typically caused by dirty tanks, unsanitary water, injuries, nutrient deficiencies, and/or exposure to other fish that are ill. If left untreated, fin rot could lead to serious health problems and even death. Luckily, it is possible to successfully treat fin rot.

But treatment should begin as soon as possible, so it is important to know what symptoms to look for as you care for your aquarium fish. At the first sign of symptoms, you can start to treat your goldfish before they become too ill. Here is what you should know about spotting the symptoms of fin rot and treating the condition if it does develop:divider1- goldfish

The Symptoms of Fin Rot

Fish suffering from fin rot in the early stages may show some white discoloring around the edges of their fins, which can be tough to spot if you are not looking for it. Therefore, you should inspect your fish’s fins regularly to make sure you do not miss this critical early sign of fin rot.

Goldfish die from toxic pollution_Amonsiri Sommut_shutterstock

Credit: Amonsiri Sommut, Shutterstock

Eventually, the entire fin area may develop a milky-white film. If the fin rot infection is allowed to fester, the fins will start to fray around the edges and small pieces of the fin may start to fall off completely, leaving chunks of fin missing.

Other symptoms of fin rot to keep an eye out for include:
  • Black or brown spots on the fins and/or body
  • Inflammation or even bleeding on the fins
  • Lethargy and loss of appetite

It is a good idea to start treatment immediately if any one of the symptoms listed here is discovered. Do not wait until multiple symptoms display themselves, as it could be too late to successfully treat the fish at that point.goldfish divider

How to Treat Fin Rot

Several things can be done to get rid of the fin rot your fish is suffering from, much of which involves making changes to the aquarium. All fish living in the same aquarium with a fish that has fin rot should be treated as if they have been infected, too. Here are the many treatment steps that should be taken once you know fin rot is present:

1. Clean the Aquarium Out

cleaning aquarium with scoop-net_Alexander Geiger_shutterstock

Credit: Alexander Geiger, Shutterstock

The first thing you should do is completely clean your fish tank out. Start by putting your fish in a temporary tank that with some of the water from the tank they live in. Then empty the water out of the aquarium and then siphon the ground gravel to remove all the waste that has been building up within it. Alternatively, you can get rid of the old gravel and replace it altogether with fresh, new gravel that has not been contaminated. Scrub the walls of the aquarium, then fill it back up with clean water.


2. Test the Water

hand holding fishing net_pritsana_shutterstock

Credit: pritsana, Shutterstock

After filling the cleaned aquarium up with water, you should test it to make sure the PH levels are balanced and that there is not too little or too much chlorine, nitrites, or ammonia present. You can purchase a water testing kit to use yourself at home, or you can bring a sample of the water to a local pet shop where they should be able to test it for you. Any water imbalances should be corrected before putting your fish back in the aquarium.


3. Treat the Fish and Aquarium

Feeding Fish and Cleaning a Home Tropical Fish Tank_steved_np3_shutterstock

Credit: steved_np3, Shutterstock

Once your infected fish has moved back into their aquarium, it is time to treat the tank with an antibiotic like Fish Aid or one prescribed by your veterinarian. This will help get rid of any bacteria left on your fish so they can heal and get back to their happy, healthy finned selves. Follow the directions on the antibiotic packaging and do not stop treatment early even if your fish looks healthy again before treatment is supposed to be completed.

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In Conclusion

The best way to fight off fin rot is to avoid it altogether, but this is not always possible. The sooner you treat your aquarium and your tank, the better chance your fish will have of surviving and eventually thriving again. So, do not wait to treat your fish for fin rot. Start the process as soon as any signs or symptoms display themselves.


Featured image credit: Nature and Life, Shutterstock