Skip to Content

Common Otocinclus Diseases and Illnesses

Common Otocinclus Diseases and Illnesses

Share this post:

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.

Otocinclus catfish can be great additions to your fish tank. You might be interested in buying some because you want good community tank fish.

They can also be a lot of fun to own if you just keep them in their own tank. For the most part, these fish are pretty easy to care for once they’ve been established in the tank.

There are problems that they can experience, though. There are various diseases that otocinclus catfish might have to deal with.

Below, you’ll learn about common otocinclus diseases. This will help you to know what to look out for so you can protect your fish.

Otocinclus Red Belly

People have reported seeing otos with red bellies. If you notice that your otocinclus catfish has a red belly, there’s a good chance that it has a bacterial infection.

Bacterial infections are more likely to occur when the water is too dirty. Water that is very dirty can stress the fish and make them sick.

You’re supposed to do weekly water changes when caring for these fish. Doing 30% water changes each week helps to keep the tank clean enough.

If you suspect that your otocinclus fish has an infection, it can be treated with antibiotics. You can reach out to an exotic veterinarian if you need advice about which antibiotics will work best.

Otocinclus Red Gills

Seeing redness around the gills is a very concerning thing. This is known as the first sign of ammonia poisoning.

Ammonia poisoning can easily kill your otos, and it’s something you’ll need to remedy as fast as you can. The ammonia levels in the tank will rise when the water is in poor condition.

It’s likely that you haven’t been doing water changes if the water is in such a state. You’re meant to do weekly water changes to keep things clean, but some people make the mistake of doing water changes too infrequently.

Ammonia levels are supposed to be at 0ppm in the fish tank when caring for otos. Get the water quality back where it needs to be.

Perform water changes and get the water quality right. Your fish might need antibiotics or antibacterial medication if they’re suffering from ammonia burns.

Otocinclus Ich

Ich is a common disease that many aquarium fish have to deal with. This is also commonly known as white spot disease.

It’s a type of parasitic infection that causes white spots to appear all over the body. The white spots can be just about anywhere, and they can even appear on the gills.

When fish contract this disease, it causes them to feel sluggish. You might notice them rubbing against objects in the tank.

They’ll also have trouble breathing and might lose their appetite. This disease should be treated by raising the water temperature, adding aquarium salt to the tank, and using medications such as Formalin.

Can Otocinclus Get Neon Tetra Disease?

Neon tetra disease is a disease that was first spotted in neon tetras. It’s a contagious condition that can pass to other fish, such as rasboras.

Can it pass to otocinclus catfish? Anecdotal evidence suggests that it can.

This is a condition that currently has no cure. If your fish shows signs of the disease, it’s best to separate it from the rest of the tank.

You should also use antibacterial treatments in the tank to try to keep the issue from spreading to other fish. The first sign of this disease is color loss.

Can I Use Aquarium Salt with Otocinclus?

Yes, aquarium salt can be used as a treatment for many otocinclus diseases. It’s common for aquarium salt to be used to speed up the healing process.

This can make it easier for otos to heal in certain situations. For example, aquarium salt is known to inhibit the parasites that cause ich.

Cotton Mold

Cotton mold is a type of fungal disease that you should be aware of as an oto owner. It’s a parasitic fungal infection that can grow on the fins as well as the body.

Sadly, this is a disease that is known to kill otos. It causes severe issues with mineral salt and water regulation.

When fish contract this disease, it causes them to act lethargic, and they will start swimming strangely. Often, you’ll notice the fish will have trouble breathing as well.

This condition can be treated, but you need to take action quickly to save the fish. Treat your otos using Formalin, copper sulfate, or malachite green.


Roundworms are parasites that can cause otos to experience organ failure. These parasites can’t grow in a tank unless the water conditions are extremely poor.

Fish that are infested with these worms will be in bad shape. You’ll be able to see worms sticking out of the anus of the otocinclus catfish.

Infected fish wind up experiencing a number of troubling symptoms. You’ll notice that the fish will have a shrunken belly, and it’ll also become lethargic.

Treating roundworms involves using medications such as parachlorometaxylenol. Levamisole is another effective medical treatment for roundworms.

Treat the water and do your best to nurse the fish back to health. Fish can survive roundworms if you take action fast.

Gold Dust Disease

Gold dust disease is yet another parasitic infection. This one impacts the gills and the skin of the otos.

You’ll see that the fish will have dusty yellow spots appear on their bodies. These spots cause the fish irritation, and it makes them want to rub against objects in the tank.

To add to this, the fish will experience breathing difficulties. You’ll likely see the fish acting lethargic, and it might stop eating entirely.

You can treat this disease with various medications. Copper sulfate, methylene blue, and Acriflavine are the best-known treatment options for your otos.

Final Thoughts

Knowing more about otocinclus catfish diseases will help a lot. Now you know what to look out for so you can protect your fish.

If your fish experience any of the problems mentioned above, it’s best to take action right away. The sooner you treat the fish, the better.

To prevent the fish from getting sick, be sure to keep an eye on the water parameters. Keep the water from getting too dirty because this can lead to issues with ammonia poisoning.

Do regular water changes, and be sure to keep your fish well-fed. It should be easy enough to keep your otos in good shape when you’re a proactive fish owner.

Share this post: