Will plecos jump out of their tank?

It’s uncommon for plecos to jump out of their tank, but in some cases, it happens. This can be because of poor water quality, overstocking, diseases, stress, or just instinct.

What to do with a pleco that has jumped out of its tank

If you have noticed your pleco laying outside of your tank, there’s a reasonable chance that it’s still alive. This obviously depends on how long your pleco has been without water, so figure out how long it maximally could have laid there.

In some cases, plecos can live for up to 30 hours out of the water, because of oxygen stored inside their stomach! So, you just noticed your pleco has jumped out of the tank, don’t panic! It’s important to take action as soon as possible, for it to have a chance to survive.

You’ll notice pretty quickly whether your pleco is still alive. Indications of this are moist skin or slight movements. If you think it’s still alive, set up a separate tub as soon as possible. This way you can take care of it and other fish won’t try to harm it. Treating it is also easier in a separate container.

Apart from putting it back into the water, there’s nothing you can do, except for hope. When it does live, check for wounds that should be treated. There’s a possibility that the fish’s slime coat has been damaged.

Why do plecos jump?

The most common reason why plecos jump is poor water quality, caused by a nitrite spike, ammonia spike, nitrate spike, or overstocking. Other reasons are stress, fights and tank size.

If you notice your pleco fighting a lot with other fish or other plecos, it might also be a cause for a pleco to try and escape by jumping.

Poor water conditions

Bad water quality is one of the biggest reasons why a pleco might jump out of its tank. It might seem odd, but they jump out looking for a new and better environment to live in.

Nitrite peak

Nitrite is an extremely toxic chemical in your aquarium and it’s part of the nitrogen cycle.

In normal cases, fish waste (ammonia) gets converted into nitrites, which immediately get converted into nitrate. If the biological balance in your tank is disturbed by f.e. overstocking, no water changes, water poisoning, a nitrite peak might occur.

Nitrites should always be at 0ppm. Any higher values are harmful to your fish.

If you notice higher values than 0ppm, immediately perform a >50% water change to lower the nitrites.

Image source: Aquascaping Lab

Nitrate poisoning

Nitrates are less harmful to fish than nitrites, but in high concentrations, they are also deadly.

As stated above, nitrate is part of the nitrogen cycle, and it’s the last step of it. Nitrates are normally absorbed by plants. 

The ideal nitrate value is between 10 and 20ppm. Nitrates shouldn’t be higher than 40ppm.

Ammonia spike

Ammonia is the first part of the nitrogen cycle, which is often caused by overfeeding.

Good ammonia levels are between 0 and 2 ppm. Any higher values might harm your plecos, resulting in them jumping out of your tank.


Overstocking can cause various problems for your pleco catfish. It causes poor water quality and fish get stressed in overly stocked tanks.

Before you buy new fish for your tank, always make sure they actually fit into the tank. You should probably not listen to pet stores, since the only thing they often care about is selling. 

Especially with plecos, which produce a lot of waste, overstocking becomes a problem really fast.

Tank size

Depending on what species of pleco you plan to get, a suitable tank is needed to make sure it can live a healthy and happy life. 

Especially common plecos are often mistreated since they can get up to 15 inches long! These fish are unfortunately sold at starting aquarists, without telling them how big they become.

A tank that’s too small increases the bioload and waste, increases stress for the fish, and doesn’t give it the swimming place it needs. 

These problems might add up, ultimately causing your pleco to jump out of its tank. 

If you are looking for a pleco that’s relatively small, a bristlenose pleco is your go! Bristlenose plecos get around 6 inches long, making the a better fit as opposed to the common pleco.

How to prevent pleco from jumping

Perform regular water changes

Performing regular water changes is a crucial part when keeping any aquarium. As we discussed before, maintaining optimal water quality is crucial to make sure your pleco doesn’t jump out of its tank, and water changes are critical for this.

You see, not all waste gets filtered out by plants or the filter. So, in order to take out access waste or nitrates, regular water changes should be done.

Regularly check your water parameters

It’s better to prevent than to solve the problems after they happened. 

Even if things in your aquarium seem fine, it’s still useful to check once in a while. An aquarium test kit is an accessory I recommend every aquarist to have, to make sure you are prepared for when problems might occur.

Use a tight lid

This is maybe the most obvious on the list, but still, a lot of people get this wrong. Adding a lid is crucial to prevent your pleco from jumping out of its tank.

And don’t be fooled, your pleco can get through much smaller holes than you think! 

Most tanks have an in-built lid with lighting, but even then it’s recommended to tape off openings.

Add hiding places

Since stress is a big factor that causes plecos to jump out of their tank, you should aim to make your pleco feel as comfortable as possible.

Hiding places are a crucial part that’s often missed, in every pleco tank. In fact, if your pleco is hiding all the time, it’s most likely because it’s stressed due to low natural cover.

My favorite hiding places for plecos:

  • Driftwood. This is the best form of natural hiding places for a pleco, for many reasons. In fact, I’ve written an entire article on this. Read Why do plecos need driftwood.
  • Plants. A full planted tank is great for plecos. Plants improve water quality and add shadow for plecos. Read our guide on the best plants for plecos (click here).
  • Stones. In particular, slate. It’s easy to make your own structures out of stones, and they fit in almost every aquarium. 
  • Pleco caves. If you like convenience, pleco caves are the best option. These are caves specifically designed for plecos to live and breed in!

Buy a spacious tank

As we’ve discussed before, overstocking and tank size is are two reasons why plecos jump out of their tank. 

It’s therefore extremely important to buy a pleco that fits in your tank, or vice versa, buy a spacious tank for the species of pleco you want to keep.

Did you know that a common pleco needs at least a 120-gallon aquarium to be happy? Other species like bristlenose plecos “only” need 20 gallons. The smaller pleco species like clown plecos can live in 15 gallon-tanks, but that’s the bare minimum.


It’s uncommon for plecos to jump out of their tank, but it certainly happens.

This is most likely due to poor water quality, stress, overstocking, or tank size.

So, in order to prevent your pleco from jumping out of its tank there are a few things you can do:

  • Regular water changes
  • Testing your water
  • Using a tight lid
  • Adding hiding places
  • Buying a spacious tank