Recognizing the signs your Pleco is dying is important to avoid the incident of having a dead Pleco in your aquarium. There are many reasons that your fish may be experiencing illness and suffering from poor health, so you need to be prepared to take care of it accordingly.

This article contains all you need to know to ensure that your Pleco remains healthy and lives till the end of its lifespan. So, keep on reading to understand Plecos and their needs better.

The Behavior of Pleco

First of all, you need to understand what a healthy Pleco looks like and behaves like. This will be very important if you want to notice any changes that might appear suddenly. Usually, it is hard for fish owners to see adverse behavior until it is almost too late.

Plecostomus sickness is not that common; they are pretty hardy fish that can survive in many adverse water conditions. However, they still need their needs met as, over time, they will develop the disease. It is much easier to care for this catfish when it is juvenile because as they grow, their size grows as well, making it a little harder to care for. Moreover, Plecos are nocturnal, which means they are only active at night and are said to be aggressive and territorial in behavior.

The juvenile Plecos are pretty shy, and they keep to themselves, but as they grow older, they become more and more aggressive. This could be due to their increasing size. The Plecos are bottom-dwelling fish, but they like to have the whole tank to themselves. It is not ideal to have them with other peaceful fish as they will attack the peaceful fish.

The Lifespan and Size of Pleco

Now, Plecos are not only very large in size, but they live for a very long time. This is why they are a long-term commitment that beginners might not be able to handle.

The average Plecostomus lifespan is around 12 to 15 years. Yup, you heard that right; they can live for more than a decade with proper care. The Plecostomus life expectancy is more than some other tropical fish that are out there. So, you have to take proper care of the fish as well.

Along with a long lifespan, the size of the fish is pretty big as well. With the proper tank and water conditions, it can grow up to 15 inches in size! This is what makes the Pleco so hard to take care of. The bigger the fish is, the harder it is to take care of, so keep this in mind before deciding to buy a Pleco.

Care for Pleco

These are basic conditions that need to be followed to ensure the Pleco can grow disease-free and healthily. The Plecostomus lifespan is, as you know, pretty long, so make sure to keep these conditions constant the whole time.

The most important is the tank size which can affect the health of Pleco negatively. A Pleco tank should be at least 75 gallons and should increase with more species of fish that you keep in the tank. Plecos also produce a lot of waste due to their huge size, so they need a tank with strong filtration. These two are the most important conditions that need to be followed at all costs.

Since the Plecos require warm temperatures, a thermometer might be required. The temperature of the water should be between 72 F to 86 F and pH of around 6.5 and 7.5. To maintain these conditions properly, have a water testing kit of good quality as these will help a lot. Besides these conditions, the tank should have enough space with well-oxygenated water. There should be driftwood and other hiding places for the fish as well. If you maintain these conditions, you should stay healthy for a long time.

Why Do Plecos Die?

Now, if you maintain the water conditions, the average Plecostomus life expectancy should be met, but there are still many other reasons you might end up with a dead Pleco.

Having a dead Pleco is a terrible loss, especially if you spend a lot of time on its setup. It’s a disappointing loss that can de-motivate you. Well, the thing is, Plecos die for a variety of reasons. Most deaths are due to inadequate water conditions that might lead to disease and depression, and eventually death. However, Plecos also die due to some other reasons like starvation, bullying, and overcrowding. So here are all the reasons that your Pleco might have died.

– Due To Starvation

Many people assume that the Plecos only need algae tabs to provide the nutrition, but that’s not true at all. Plecos need a balanced diet of fresh and blanched vegetables along with shrimps and shrimp pellets to survive.

Therefore, you can’t keep the Pleco satisfied with only a single diet item. They need a balanced diet with many different components, just like humans. One more thing is that they need to be fed at night since that is when they are the most active. When you keep Pleco with other fish, make sure that they are getting their share of food. One sign is when the Pleco looks pale.

If the dead Pleco that you found in your tank had a concave stomach or the Pleco looks pale, well, it died due to starvation most probably. Starvation is easily avoidable by making sure to do your research and find out all the food items they eat instead of assuming that the Pleco only needs algae in the tank to feed on.

– Due To a Defect

Now, this is a reason for death that was out of your control. If your Pleco was kept in the perfect environment with plenty of food and good filtration but still died shortly, it might be due to the defect in the fish.

Many types of defects can be present in the fish. You might notice that your Pleco died overnight without any reason. Now, it could be because the fish was already sick when you bought it from the pet store, and you didn’t notice.

Another reason for the defect might be genetic complications, and you just got a fish from a bad batch. Again you can’t control this. However, this is why you should always buy from a reputable seller, even if the fish is a little more expensive. These defective fish die soon because they can’t take the stress of the transition as they are already very sick and weak.

– Too Much Food

Plecos and other fish require plenty of food to survive, so many people think there is no such thing as too much food for your fish. This is very far from the truth. Too much food can be bad for the Pleco, just like starvation.

There are many ways too much food can lead to Plecostomus sickness and death. The most common reason is when the tank water gets dirty, and your filter is not strong enough to filter the water. The dirty water has too little oxygen for the fish leading them to get sick and die. This is why fish should be given an appropriate amount of food for a couple of minutes, and then the rest should be removed.

Another way that too much food can be harmful is by making the fish unhealthy. Obesity is very bad for the fish, and it will not be able to move as much, which can again lead to disease or death. Moderation is the best when it comes to food, along with providing the best nutrition-filled food.

– A Sudden Change

This was for when your Pleco died after a water change, and you don’t know why. I mean, aren’t water changes very necessary for the fish to survive? Yes, however, it has to be done properly, or it can lead to a dead or extremely sick Pleco.

When you have a dirty tank, the chemical and physical change in the water is very slow. Slow enough for your fish to get used to it. Therefore, performing a huge and sudden water change can be deadly for the Pleco. The fish often cannot tolerate this change, so the ones that do survive are very sick.

So what should you do? Perform small water changes slowly so that there is no sudden change in the water. This is why partial water changes are recommended for fish. Moreover, if you take care of the quality of water, these changes will have no drastic effect on the health of the fish.

– Too Many Chemicals in the Water

Just like most fish, the Pleco is extremely sensitive to some chemicals in the water. Namely, ammonia and nitrate are harmful chemicals. Even small amounts of these chemicals can be deadly for the Pleco, which is why it has to be zero.

These chemicals affect the gills of the fish, making it hard for them to breathe. This alone is very deadly for the fish, but these chemicals also cause stress in the Pleco. The leading cause of ammonia and nitrate is the leftover food that rots. These chemicals will eventually kill the fish unless immediate actions are taken. So, make sure to have a water testing kit to keep these chemicals absent from the tank. If your tank is very dirty, there will be protein foam on the surface of the water.

– Having Dead Tank Mates

First of all, you need to know why the tank mate died, so you should already remove it. However, for whatever reason you don’t, it can pollute the water and cause disease.

A dead tank mate is terrible for the tank, and if it suffers from the disease, the other fish like your Pleco can also get the disease if it is not taken immediately. Along with that, the fish will decay in the water, causing bacterial and algae growth, which will affect the pH of the water. This, just like decaying food, will cause gill problems as well as stress for the fish. If removed, the fish might survive, but if not, they will die due to the pollution.

This is why you should check on all your fish in the tank daily. Make sure none of them is missing or not showing up for food. Of course, sometimes they could just be hiding, which is why a thorough search of your fish is important. Along with that, understand the behaviors of all the fish so you can notice if any of them is acting weird.

– Wrong Water Conditions

All the fish need their natural habitat replicated for them to live happily in the tank. Although Plecos are considered hardy fish, too much water parameter fluctuation can lead to disease, stress, or even death in them.

The pH of water, water hardness, and temperature of the water need to be very close to the natural habitat where they came from. Along with water parameters, the tank size is just as important. A small tank will cause a very stressful situation which can also kill the fish. The biggest reason for Pleco’s death is due to stress.

Stress is caused by the wrong parameters and fluctuating water conditions and due to some other conditions. Having aggressive tank mates, disease, underfeeding, and all such situations can lead to a dead fish. Signs of stress are Pleco turning white, hiding too much, weight loss, and much more. Notice the signs and make sure to improve their condition before they die.


Plecos are pretty easy to care for, and following all the water conditions will not lead to any disease. Here are some things to remember from the article:

  • Plecos are pretty hardy fish that can survive in many adverse water conditions but can still be susceptible to some common freshwater fish diseases.
  • The average Plecostomus lifespan is around 12 to 15 years, and it can grow up to 15 inches in size.
  •  Plecos die due to overfeeding, starvation, wrong water parameters, ammonia and nitrate in the water, and other such causes.

Being an aquarist requires more than having the appropriate tank and the money to buy fish pellets; it needs your commitment to learn as much as you can about fish keeping. You reading this is a sign that you are on the right track.

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