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How to Treat Mouth Rot in Angelfish

How to Treat Mouth Rot in Angelfish

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.

You might have purchased angelfish because you heard that they are easy to take care of. These fish are indeed hardy and pretty easy for beginners to keep in fish tanks.

It’s important not to let this information lull you to sleep, though. You do need to take care of the angelfish well if you don’t want to encounter various problems.

There are certain angelfish diseases and problems that can pop up if you aren’t careful. Some beginners have even noted that their angelfish have experienced what looks to be mouth rot.

If you’re seeing signs of mouth rot in your fish, then that’s something that you cannot ignore. It could be a serious problem that might even kill the angelfish if you don’t act.

To make matters worse, mouth rot issues are often very contagious. Read on to learn more about this situation so that you can figure out how best to proceed.

Understanding Angelfish Mouth Rot

Angelfish mouth rot is a fungal disease that is caused by gram-negative bacteria. The bacteria is normally present in the fish tank, but it doesn’t present a problem.

Things only become problematic when a fish is wounded or when it has a weakened immune system. There are various reasons why a fish might have a compromised immune system.

Fish that are experiencing stress will not do great in fish tanks. Stressed fish will have their immune systems weakened, and this makes them more susceptible to various conditions.

If a fish with a weakened immune system gets wounded, then it could be exposed to the bacteria. This could then lead to issues with disease.

Sometimes the disease impacts the fish’s mouth, and this is what is known as mouth rot. Mouth rot is caused by bacteria, and it is able to enter the fish’s body through wounds.

Angelfish might get wounded by fighting each other. This happens a lot when you have multiple male angelfish in the same tank, but you could also have aggressive tankmates that don’t mesh well with the angelfish.

What Are the Symptoms of Fungal Mouth Disease?

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

There are various symptoms that you can look out for. Try to pay attention to the face and mouth of the angelfish to see how it’s doing.

If you notice fluffy threads that are off-white and sort of like cotton near the face, then that’s a sign of fungal disease. It could also appear near the mouth or the gills.

You might see that the fish’s fins will look different than usual. The fins might appear to be somewhat ragged.

Fish who are having problems with fungal mouth disease will have issues breathing, too. You’ll likely notice rapid breathing because the fish is trying to compensate for the infection.

On the fish’s head, you’ll likely see increased mucus production. The gills will also produce a fair amount of mucus when they’re infected.

Advanced cases of fungal mouth disease will cause sores to form on the fish’s body. Generally, the lesions will be near the face since that is the infected portion of the body.

How Do You Treat This Condition?

Treating this condition should allow the fish to get better. However, you’ll get better results if you catch things early.

If you let the fish stay infected for too long, then it could wind up suffering complications and dying. In fact, it’s very common for fish to die when they experience mouth rot.

Getting things better will involve treating the fish with antibiotic or antibacterial medication. You might wish to consult an exotic veterinarian to get specific information about recommended treatments.

This will ensure that you get the best medicine for your angelfish. You’ll also be able to ask questions about how best to deliver the medication as well as how much medication you should use.

Typically, medications will be given to the angelfish for seven days. After the seven days have passed, you should notice the fish will be improving and starting to look healthier.

Another thing that can help is adding a bit of salt to the tank. It’s said that adding one ounce of salt per gallon of water is a good way to prevent the disease.

Prevention Advice

Cleaning Fish Tank Water

You likely want to keep your fish from ever experiencing mouth rot. Thankfully, there are some things that you can do that will help you to protect the fish.

The first thing to focus on involves keeping the tank clean. A clean tank is going to be less likely to have excessive amounts of gram-negative bacteria.

Some bacteria being present in the tank is normal, but a dirty tank will have more issues. You should do your best to clean the tank regularly, and it’s important to change out water a bit at a time either weekly or bi-weekly.

Also, keep an eye on the water parameters to protect your fish. You need to keep the pH balance in the right range for the angelfish while also monitoring the temperature.

If the water balance gets thrown off in some way, then it could cause the fish to go through stress. This can harm the fish’s immune system, and it’ll then be more susceptible to mouth rot.

You should also consider taking steps to keep the fish from getting wounded. Avoid putting two male angelfish in the same tank since males tend to fight over territory and other things.

If you have aggressive tankmates in the same tank as the angelfish, then you might want to make some changes.

The angelfish are likely getting mouth rot due to bacteria getting into wounds. If the fish can avoid getting wounded as much as possible, then you’ll have less to worry about.

Final Thoughts

Mouth rot is a fungal issue, and it can be problematic if you don’t know how to fix things. Luckily, you should be able to help the fish out by giving them antibacterial or antibiotic medications.

Taking steps to protect the fish should help to prevent issues with mouth rot. Keep the fish from being stressed and do your best to clean the tank regularly.

So long as you’re a proactive fish tank owner, it’s likely that you won’t have to worry about mouth rot too much. If you continue to have issues, then you might need to keep a closer eye on water parameters to ensure that you aren’t making mistakes.