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Why Do My Otocincluses Keep Dying? (6 Common Causes)

Why Do My Otocincluses Keep Dying? (6 Common Causes)
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 want to have a good experience with otocinclus catfish, but sometimes they can be a bit finicky. Many people have a hard time keeping these fish alive.

If your otos keep dying, you might be wondering what’s going wrong. Is it something that you’re doing that’s causing the fish to die?

Below, you’ll learn about many reasons why otos might die in a fish tank. This should help you to figure out what’s going on in your situation.

Use the information to troubleshoot and determine what changes you might need to make. Hopefully, it’ll allow you to have an easier time keeping the fish alive since you’ll know what mistakes to avoid.

Why Are My Otocincluses Dying?

Having your otos die is something that’s going to bother you. There’s a good chance that you’re unsure why this is occurring.

What issues would cause the otos to die suddenly? Are there common reasons why these fish die?

There could be many different things happening. You can use the information below to figure out what’s likely going on with your otos.

1 – Problems Being Introduced to Tanks

Otos commonly have problems when being introduced to new tanks. It isn’t 100% understood why, but these fish are known to suddenly die when being put in new fish tanks.

This doesn’t always happen, but it’s something that can occur. It’s speculated that it might be due to the stress of being transported.

To keep otos alive, you’ll need to care for them very carefully early on. You need to make sure that you monitor the water parameters and give the fish what they need to become established in the tank.

After the first month, the otos should acclimate to the tank and they’ll be much more hardy. Just make sure that you keep a close eye on them during the early days.

2 – Stress

Stress is something that can easily kill your otos. You need to be careful not to let these fish get overly stressed.

Of course, stress is something that can easily kill most types of fish. When fish get stressed, they’re more likely to become sick.

It compromises their immune systems and makes it so they might get infected or experience other issues. There are many things that can make fish feel stressed.

Living in dirty water is something that can make fish stressed. Otos love eating algae, but the water still has to be clean enough for them to thrive.

You need to clean the tank and do weekly water changes. Overcrowding the fish tank can stress these fish, too.

Putting otos in fish tanks that don’t have plants will make them feel stressed. Otos need to live in planted tanks because they like hiding and they enjoy eating algae directly off of plants.

Do your best to recognize sources of stress. Make necessary changes so your otos can thrive instead of dying due to excessive stress.

3 – Disease

It makes sense that otos might die because they’re sick. Your otos might keep dying because they’re getting sick in the tank.

There are many diseases that these fish are susceptible to. Some of them are minor while others are a bit more serious.

Even minor illnesses can wind up killing fish if you don’t treat them, though. For example, a fish might contract ich, and it can get better if you treat it with medications and aquarium salt.

If you do nothing, the fish will continue to suffer. It’ll have trouble breathing and the problem will just get worse.

When you don’t pay attention to such issues, the fish might die. So you need to pay attention to what’s happening in the tank so you can help your fish if they happen to get sick.

4 – Issues With Tank Mates

Problems with tank mates might be what’s killing your otos. People commonly buy otos to put them in community aquariums.

These fish are great in community fish tanks, but they’re so peaceful that they might get bullied by more aggressive fish. This is why it’s imperative to research the compatibility of the fish before putting them in a fish tank.

Since otos would rather run and hide than fight with other fish, they’re not going to stand up for themselves. If you put otos in the tank with the wrong type of fish it’ll be a recipe for disaster.

Otos aren’t too big either and they can be eaten by fish that are a bit too large. You need to choose tank mates that will get along well enough with the otos.

It’s also worth noting that minor bullying issues can lead to the otos getting stressed. This might be enough to kill them if they’ve just been introduced to the tank due to how fragile they are in the early days.

5 – Not Enough Otos in the Tank

You need to keep enough otos in the tank so they can feel comfortable. These fish aren’t meant to be kept by themselves and you can’t even keep them in pairs.

Otos are shoaling fish that live in huge groups in the wild. You’ll find them living with thousands of other otos in the wild, but they’re okay living in groups of six or more in a fish tank.

If you’re keeping too few of them in the tank, they’ll become rather stressed. This will lead to health complications and the otos will eventually die.

Don’t make the mistake of keeping only a couple of otos in the tank. If you don’t have room for at least six of these fish you shouldn’t buy them.

6 – Starvation

Starvation is something that some don’t realize they need to worry about with otos. Otos are often bought specifically to take care of algae in fish tanks.

It’s true that these fish love to eat algae. They’ll primarily eat algae and biofilm in the tank.

Otos can run out of algae and biofilm to eat, though. Also, you’re supposed to give them supplementary food a few times per week.

These fish should be fed algae wafers and blanched veggies a few times per week. This will ensure that they’re getting the nutrients that they need to thrive.

Otocinclus Playing Dead

Make sure that your oto isn’t playing dead at the bottom of the tank. Many fish owners have noted that these fish will sometimes lay motionless at the bottom of the tank and look dead.

You shouldn’t assume that the fish is dead right away. Look to see if the fish is breathing and give it some time.

Try touching it to see if the fish moves when you gently poke it with the fish net. If it’s truly dead, it’s not going to react at all.