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Why Is My Angelfish’s Dorsal Fin Split? (3 Common Reasons)

Why Is My Angelfish’s Dorsal Fin Split? (3 Common Reasons)

This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addtion, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Angelfish are certainly among the most popular pet fish. They’re very pretty, and they aren’t too hard to care for, all things considered.

Taking care of your angelfish is important, though, and you want to try to do the best that you can to ensure that the fish stays around for a long time. Sadly, there could be complications with the angelfish from time to time.

If you do your best to care for the angelfish, then you’ll be able to avoid most issues. However, you might be surprised to see that your angelfish has a split in its fin.

This is certainly a reason to be alarmed, and you’re likely not sure why it happened. What causes the dorsal fin to split this way?

Keep reading to learn about angelfish fin splitting issues. You’ll be able to discover why this might have happened so that you can try to keep it from happening to other fish in the future.

1 – Dietary Issues

Angelfish Eating

Dietary issues have been known to cause dorsal fin splits in angelfish. If your angelfish isn’t eating the right type of food, then that could be why you’re noticing problems such as this.

Try to think about whether you’re feeding the angelfish properly or not. Have you been feeding the fish regularly or have you been waiting several days to feed it?

Generally, it’s recommended to feed an angelfish once or twice per day. Experts say that younger angelfish like to eat a bit more often, so if your fish isn’t yet an adult, then it might be prudent to feed it three times per day.

While it’s true that an angelfish can go at least three days without eating, it’s not going to be good to only feed it every two or three days. To ensure that the angelfish is getting the nutrition that it needs, you should be feeding the fish multiple times per day.

It’s good to get used to feeding the fish at the same time each day. This will keep you from making mistakes since you’ll just fall into a routine.

Of course, what you feed the fish is just as important as remembering to feed it. If you’re not feeding the fish the proper things, then that could be the cause of the fin-splitting issues.

Angelfish should be eating special angelfish preparations that you get from the pet store. You’ll likely be buying fish flakes that are meant for angelfish as well as shrimp pellets that you can give to your fish.

Some angelfish owners also choose to feed the fish live shrimp, frozen shrimp, and live worms from time to time. It might be beneficial to mix up what you’re feeding the fish every so often.

If you need specific advice about what to feed the angelfish, then asking for expert help is a good choice. You can talk to an exotic veterinarian to get more details.

Professionals such as this will know the best types of fish food to help angelfish thrive. You can also discuss the fin-splitting issue so that you can determine if the fish’s diet is truly to blame.

2 – Fungal Infection

Cotton Mouth Fungus on Black and Yellow Angelfish
Cotton Mouth Fungus on Black and Yellow Angelfish

Fungal infections can also cause fish to experience dorsal fin splits. When fungal infections are present at the end of rays, the fin will start to split as the fish swims.

If you suspect that fungal infection is an issue in your tank, then you’ll need to treat the tank. You can purchase antifungal and antibacterial chemicals that will help the tank to get back to normal.

You want to try to keep the fish from getting sick. It’s possible that you didn’t keep the tank clean enough, and this caused fungi and bacteria to form at various points in the tank.

Fungus and fin rot can occur when fish get wounded and are exposed to bacteria or fungus. Your fish might be getting into fights with other fish, and this will leave them with small wounds that then get infected.

If your fish are fighting, then you might need to take steps to address that. For example, you could be keeping too many fish in a small tank.

Also, male angelfish don’t get along well when placed in the same tank. Two males will fight over territory, potential mates, and just about anything else.

Treat your fish tank and test the water to get everything back to normal. If you can get things back to normal, then the fin might be able to heal and look healthy again.

3 – Too Much Water Flow

Blue Zebra Angelfish in Bubbly Water

Another thing to consider is whether too much water flow in the aquarium could be to blame. You might have the water flow so high in the tank that it’s just too much for the angelfish to take.

Some types of angelfish are a bit more delicate than others. Veil angelfish are not going to do well if the water flow is too powerful in the tank.

It can cause the fins to split, and then the fish will look to be in bad shape. If you can correct things and make the water flow more manageable for the fish, then everything should be fine.

Both veil and superveil angelfish have a tough time with water flow issues. Be mindful of this so that you can avoid these problems.

Final Thoughts

There are three situations that are likely to cause dorsal fins to split on angelfish. The most likely scenario involves the fish tank having issues with fungus and bacteria.

If an angelfish is injured, then it could have wounds that will become infected by bacteria. A fungal infection could very easily cause its dorsal fin to split.

Dietary concerns could also be to blame. If you don’t feed the angelfish well, then its lack of nutrition could keep it from being able to generate the cartilage that it needs for its fin.

Water flow strength issues could cause veil angelfish to get split fins, too. You’ll want to do your best to protect your angelfish and give them an environment where they can thrive.

Hopefully, this information will make it easier for you to take care of your fish. Keep all of this in mind and you should be able to turn things around so that your fish will heal up.