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9 Common Discus Fish Diseases and Illnesses

9 Common Discus Fish Diseases and Illnesses

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

Discus fish are great to own because they’re pretty fish that stand out in your aquarium. You need to do a great job taking care of the fish to keep them safe, though.

These fish have a reputation for being delicate. If you don’t care for them well they can become stressed and they might get ill.

Certain diseases and illnesses are known to impact discus fish. Read on to learn about the most important ones that you should be aware of.

This information should make it easier to keep your fish safe. If you recognize signs that your fish are getting sick, it’ll be important to act fast to save them.

1 – Hole in the Head

Hole in the head disease is a terrible illness that you don’t want your discus fish to experience. This is a disease that can easily kill discus fish if you don’t treat it fast enough.

Sometimes this condition is also referred to as head and lateral line erosion. This disease is caused by parasites and you’ll notice lesions appearing on the head of the fish.

It can look truly gruesome as the disease progresses. Your fish will look like its head and lateral line are literally eroding.

Generally, this condition is caused by a nutrition deficiency. Discus fish become susceptible to the parasites that cause hole in the head disease when they aren’t being fed properly.

To avoid issues, it’s best to focus on feeding your fish well at all times. Do your best to give your fish an appropriate diet.

Hole in the head disease can be treated using medicines such as Metronidazole. Treat the condition as soon as you recognize that there is a problem.

2 – Fin Rot

Fin rot is a very common condition that discus fish have to deal with. This is a type of bacterial infection that causes the fish to experience rot.

You’ll notice that its fins will start to look as if they’re rotting away. The bacteria is eating away at the flesh of the fish and it’ll make your discus fish look terrible.

There could be a problem with bacteria buildup in your gravel. This is causing the fish to get sick.

Generally, this only occurs when you don’t do an optimal job keeping the tank clean. You might have neglected tank maintenance.

Medication can help to clear things up, but you must also focus on fixing issues with water quality. Discus fish can recover from fin rot, but it’s possible that the fish might experience permanent disfiguration.

3 – Gill Flukes

Gill flukes is a type of parasitic disease that you should be aware of. This is caused by small white parasites that have a very worm-like look.

Fish that get gill flukes will often have difficulty breathing. It’s normal to see a discus fish breathing very fast when it has gill flukes and this is usually because of inflamed gill tissue.

Your fish might lose weight and it could even experience wounds on its body. Both eye wounds and fin wounds are commonly spotted on fish that have gill flukes.

Luckily, you can treat gill flukes to help your fish get better. Formalin is one of the most common medications that’s used to treat this problem.

It’s also normal to treat this issue using aquarium salt. Do your best to focus on water quality to help your fish get back to normal.

4 – Ich

Ich is another common disease that many types of fish can get. Discus fish can also experience ich and it will be a very annoying disease.

This is a parasitic disease that causes white spots to appear all over the body. The white spots can show up on the body, the fins, the gills, and just about anywhere else.

Fish that are dealing with this condition will become lethargic and they might stop eating. It’s normal to see them rub against objects to try to find relief as well.

Rapid breathing might be noticed when the fish has white spots on its gills. You’ll want to treat ich as fast as you can to help the fish get better.

Ich can be treated by giving the fish medication and raising the temperature of the water slightly. Aquarium salt is a common treatment for ich as well.

5 – Velvet Disease

Velvet disease is also referred to as gold dust disease and rust disease. It’s a type of parasitic condition that causes fish to have a brownish-gold film cover their bodies.

Your fish might look a little bit dusty when it has velvet disease. It’s possible that the fish might take on an opaque appearance as well.

Fish with velvet disease usually get skin ulcers. You’ll also see that the fins will be clamped to the body.

Weakness, general lethargy, appetite loss, and weight loss are all signs of velvet disease to be aware of. Eventually, the skin will start to peel off of the fish when the disease advances.

This parasitic infection usually only impacts discus fish when they’re living in tanks with poor water quality. So you can prevent velvet disease issues by focusing on tank maintenance and regular water testing.

If your fish already has velvet disease, it’s important to treat it as soon as possible. There are medicines that can help, but you need to fix water quality issues while also treating the tank with aquarium salt.

6 – Discus Plague

Discus plague is a terrible viral infection that can kill your fish. This can be spread from one tank to another and you need to be very careful.

Researchers believe that discus plague is essentially a type of herpes virus. It’s known to impact discus fish, angelfish, Oscars, and severums.

When fish contract this disease you’ll see them breathing rapidly. Sometimes the fish will swim up and down in the corner of the tank for no discernible reason, too.

You might see black spots start to form on the fish. Eventually, the fish will lose its appetite and you’ll see that it has clamped fins.

Excessive mucus production is a common sign of discus plague. You’ll also notice the fish flashing.

Sadly, there isn’t a true cure for this disease since it’s a virus. The plague virus doesn’t usually kill fish directly, but it’ll negatively impact the immune system and make it more likely that your fish will die from other causes.

So fish that get discus plague often die from other illnesses. All you can do is boost the immune system of the fish as much as possible and focus on providing excellent care to help the fish live as long as possible.

7 – Cloudy Eye

Cloudy eye is a discus disease that is caused by a bacterial infection. Typically, this only happens when the water quality is very low.

When you don’t take care of the water properly, it can cause ammonia, nitrate, and nitrite levels to rise in the tank. This can lead to bacteria living in the water that might infect your fish.

Eventually, you could see issues with cloudy eye disease pop up. When this happens you’ll likely notice a white film covering the eyes of the fish.

Some describe the eyes of the fish as having a milky appearance. It’s important to diagnose and treat this problem early so the fish can survive and get better.

Generally, you’re supposed to solve issues with water quality to help the fish improve. Aquarium salt can be used as a treatment as well.

Do better to maintain high water quality in the future to avoid such problems. Stress also has the potential to make fish susceptible to these bacterial infections.

8 – White Poop

What if you notice that your fish has white poop? This is a common sign of many different diseases.

Fish that have ich are known to produce white and stringy poop. This is also fairly common among fish that have hole in the head disease.

Whenever you notice unusual poop appearing in the tank it’s best to take notice. It could be an early sign that your fish is sick.

Observe the fish and try to determine what type of illness it has. Take the appropriate action to treat the fish so you can keep it alive.

9 – Body Rubbing

When fish start rubbing their bodies against objects in the tank it’s known as flashing. This is something fish do when they’re uncomfortable.

Most commonly, fish rub their bodies against rocks, tank walls, and other objects when dealing with parasitic infections. For example, a fish that has ich will likely do this.

It’s thought that fish do this because they’re trying to remove the parasites. They could also be trying to find some relief.

How to Deworm Discus Fish

The best way to deworm discus fish is to use appropriate medication. Many enthusiasts recommend using deworming medications every so often as a precaution.

Some of the most common medications that people use include fluebendazole and fenbendazole. You can ask for specific recommendations from an exotic veterinarian that handles fish if you’d like to learn more.

Can You Use Epsom Salt for Discus Fish?

Yes, using Epsom salt as a treatment is very common. Discus fish can be helped by being treated with aquarium salt or Epsom salt.

There are many diseases that can be treated using the salt method. Of course, you’re always supposed to follow the recommendations carefully.

It’s unsafe to put too much salt in the tank. So you need to be sure that you follow the instructions and do things right.

How to Quarantine Discus Fish

Quarantining discus fish will be simple enough. Simply set up a quarantine tank that is separate from the main tank.

This tank should be cycled and it should have the appropriate water parameters for discus fish. It’s also wise to ensure that the quarantine tank is big enough.

Remember that these delicate fish hate being cramped. So a slightly larger than usual quarantine tank isn’t a bad idea.

Often, people use aquarium salt in quarantine tanks to treat sick fish. Focus on maintaining good water quality and monitoring the fish while keeping it in quarantine.

Final Thoughts

It’s important to do your best to prevent discus fish from getting sick. Since these fish are fragile they might die when they get sick.

While you can sometimes save the fish when they become ill, there is no guarantee that the fish won’t die. It’s better to try to keep the fish from getting sick in the first place.

Focus on keeping the water very clean so your fish won’t be susceptible to illnesses. Also, you need to feed the fish well to keep them from being malnourished.

If you focus on providing excellent basic care, it’s less likely that the fish will get sick. When you notice signs of illness, do your best to take action immediately.

Treating illnesses fast will give the fish the best chance of survival. It’s more likely that everything will be okay if you’re on top of things.

Those who don’t pay much attention to their fish won’t catch these problems on time. So it always pays to be an attentive owner who monitors what’s going on in the aquarium.

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