a black and white Plecostomus resting at the bottom of their aquarium

Are you a new aquarium owner looking for the perfect fish to add to your tank? If so, you may want to consider the Plecostomus. This unique fish is an excellent choice for beginner aquarists and can make a great addition to any tank.

The Plecostomus, or “Pleco” as they are often called, belong to the family Loricariidae and are native to South America. They are a popular choice for aquariums because of their hardy nature and interesting appearance. Plecos come in a variety of colors and sizes, ranging from the small “Dwarf Pleco” to the large “Common Pleco”.

Plecostomus are great fish for your family’s aquarium for many reasons. First, they are easy to take care of. They’re not picky and the only thing they require is a lot of water to swim in. They can save you money by not needing an expensive filter. The Plecostomus doesn’t need a fancy filter because they are the filter eating up everything at the bottom of your aquarium. Third, they are very low maintenance. 

Plecos are bottom-dwelling fish that feed on algae, making them ideal for tanks with algae problems. They are also peaceful fish that get along well with other tankmates, making them a great choice for community tanks.

Plecostomus are like a vacuum at the bottom of your aquarium. They do a lot to keep your aquarium clean and keep all the bad waste chemicals to a minimum between water changes. They do a lot to help keep the overall health of the other fish high.

They are not very active and will spend most of their time hanging out at the bottom of their tank. They have a pleasant disposition. They are not as aggressive as other types of fish and they don’t nip the fins of other fish.

A Plecostomus isn’t a fish that many think about when you’re looking to add a new member to your aquarium. But they really should be because they are a great fish for even the most experienced aquarium owner. 

You can purchase a Plecostomus for between $5 and $8.

Plecos are a great fish, because they are active during the day and are easy to find in your aquarium. They are also relatively low-maintenance, requiring only occasional feedings of algae wafers or blanched vegetables.

Overall, Plecostomus are an excellent choice for beginner aquarists. They are hardy, peaceful fish that can help keep your tank clean and make a great addition to any aquarium. So if you’re looking for the perfect fish for your tank, consider adding a Plecostomus today!

Information about Plecostomus

  • Average Length: Up to 15 inches
  • Scale Colors: Gray, Green, White and Black.
  • Attention Needs: Low
  • Tolerance to Heat and Cold: Yes
  • Good Pet: Yes!
  • Good with Other Plecostomus: Yes but their large size makes it difficult to keep them together.
  • Good with Other fish species: Yes
  • Good for Less Experienced Pet Owners: Yes
  • Health Concerns: Cloudy Eyes and Ich
  • Allergies: None 
  • Average Life Span: 10 to 15 years

Physical Appearance of Plecostomus

several large Plecostomus at the bottom of their tank

Plecos have an elongated body with large pectoral, dorsal and tail fins. Their dorsal fin has seven soft rays and one coarse ray while the anal fins have 3 to 5 soft rays and one coarse ray. The rays are bones within their fins that hold their shape and keep them from flopping around like fins in goldfish. Their tail fin is shorter at the top and longer at the bottom. Their dorsal fins also have spines on them that are used for protection against aggressive fish.

A special feature of the Plecos is that they have large bony plates that cover their bodies. Because of their plates, they are often called ‘armored catfish’. Their bony plates along with the spines on their fins act as armor that helps protect the Plecos from predators in the wild.

These fish have a large head with a sucker shaped mouth, often called ‘suckermouth.’ The unique shape of their mouth allows them to breathe, feed and attach themselves to surfaces at the same time. The different functions of their mouth helps them survive in a diverse range of conditions.

Their eyes are high on their head with a unique membrane covering them that helps regulate the exposure of light in their eyes.

There are hundreds of species of Plecos with several color variations like black, white and green. They can have patterns like solid, striped or dotted. The most common Plecos have a gray color with a brown and sand-colored pattern or spots on their bodies.

The Plecos can grow up to 24 inches in their natural habitats but in captivity, they will only grow up to 15 inches.

When viewed from above, the females are larger than the males and seem to have a rounder body than the males slimmer bodies.

Temperament of Plecostomus

an orange Plecostomus stuck to the side of their aquarium

Plecos are nocturnal fish and will be most active during the night. They will spend days hiding behind the plants or caves placed inside their tank.

They are slow-moving fish who prefer to stay at the bottom of their aquarium.

They do not act aggressively towards other fish species. If they feel threatened, they will just swim away.

Plecos also tend to be good tank mates but their large size is an impediment. They can grow up to 15 inches long, making them one of the bigger freshwater fish many will own. The best way to keep them is making sure their tank is large enough for not only them, but all the other fish you plan to have.

Plecos tend to be timid, for the first few days after introducing them to a new tank they’ll spend a lot of time hiding between tank decorations or under plants. They’ll spend less time hiding a few days after being introduced to a new tank.

Best Habitat for Plecostomus

Plecostomus are native to South America and are found in a diverse range of conditions in the wild. Most of these fish live in fast-flowing streams and rivers that have a rocky substrate but some are also found in brackish estuaries. As mentioned before there are several species of Plecos and each may have their own needs. So do your research before setting up their tank. 

Plecos tend to attach themselves to tank walls. They can easily scratch the acrylic tanks with their spines and mouth, we recommend keeping them in a glass tank to reduce scratching. 

Tank size

an orange Plecostomus sucking a rock in their aquarium

Plecos are just 2 to 4 inches long when they are young, and can be kept in a small tank of 10 gallons. The size of their tank depends on the species you get. The smaller Plecos – Otocinclus will not grow more than 2 inches and can be kept in a 10-gallon tank even when they mature. Some species can grow up to 15 inches and will need a much larger tank when they are fully matured. For example, Hypostomus Plecostomus will need a tank a minimum of 100 gallons when they are fully grown. 


The ideal water temperature for the Plecos is between 72 to 86° F. Most other fish that they will share an aquarium with will live in the higher end of this range. Because they can handle such a wide range of temperatures they can be kept with just about any other fish.

pH Level

The pH level should be in the range of 6.5 to 7.5. 


Plecos need a tank with subdued lighting conditions. Floating plants can help lower the lighting at the bottom of your tank. The lights should not be on more than 8 to 10 hours a day. Adding a timer to your lights will make it easy to maintain consistent lighting inside your fish tank.


Plecos like to feed on Algae and will need a number of plants in their tank to help grow the algae. Plants with broad leaves like Java Fern and Anubias are recommended because they can eat algae right from their leaves. 

2 green with white spots Plecostomus resting on the small rocks at the bottom of their aquarium

These fish like to sleep during the daytime and they will need plenty of hiding places inside the tank. Overturned flower pots, caves, or hollowed logs are all great for creating hiding places for them.

Their tank should have driftwood because Plecos like to nibble on them.

Tank conditions

To simulate their natural fast river water conditions, try to create a strong water current inside the tank. A canister filter is one of the best ways to move a lot of water and create a current in your aquarium. The canister filter isn’t needed for actual filtering because the fish does a great job cleaning, the canister is only needed for the current. The good news is that the Pleco does a lot of the cleaning for you. Because they do most of the heavy lifting you shouldn’t need to clean the canister filter often.

Plecos will mostly stay close to the bottom of your aquarium and their main source of food is mostly scavenged food or other waste from the substrate. Using gravel or soft sand as a substrate for your aquarium will help the Pelcos filter through the substrate and find food.

Tank Maintenance

Water conditions like temperature, pH level, and dissolved organic compounds should be monitored daily. Make sure the water filters are running properly and are efficient at cleaning the water. A water testing kit is needed to check the tank conditions.

Plecos are natural algae eaters and they will also eat decaying plant matter or dead fish that fall to the bottom. With them eating all of this, the aquarium will stay cleaner longer.

A 10 to 25 percent water change should be performed every other week.

a large black Plecostomus resting on the gravel at the bottom of their aquarium

Best Tank Mates for Plecostomus

Young Plecostomus are community fish. They are peaceful and will not act aggressively with other fish species.

Popular tank mates for Plecos are:

Avoid keeping Angelfish and Discus with young Plecos because they can nip at them. Smaller fish species that can fit in their mouth should also not be housed with them because Pelcos can eat them.

A major concern while deciding on a community for them is that they will get very large and outgrow other fish in their tank. More than one Pleco should not be kept in a single tank because they will need a very large tank!

Health Issues

Signs of a healthy Pleco are:

  • Clear eyes
  • Will have the ability to attach to glass or rocks
  • Remain close to the bottom
  • Eats actively
  • Has bright colors

Always check your fish for the above characteristics before buying them. An unhealthy fish can spread contagious diseases to other fish in the tank and also impact the water quality.

Cloudy Eye

As the name suggests the fish will have a whitish or grayish cover in their eyes. It will impact their visions and you may see the Plecos swimming in an unusual way. Some may also have a faint coloring on their body. Cloudy Eyes are usually a result of poor water quality and improving the water conditions will help take care of the disease.

As you can guess by the name of the illness, the fish will have a white or grayish obstruction in their eye. Obviously this makes it difficult for them to see clearly. Because of the number of different reasons for the cause, it can be difficult to know what the cause is.

Trauma to the eye is the main cause for healthy fish to have this condition. The problem is that it can be difficult to know that this was the cause. Sometimes trauma to one eye can result in both eyes becoming cloudy. So while this is the main cause, you should come back to it after exploring other things that you can test for.
The next most likely cause is poor water quality. The water in your aquarium should be checked regularly to make sure that it’s both clean, and that invisible contaminants are not building up.

Diet seems to be the next most likely cause. Review what your fish should be eating and make sure that they are eating enough. Fish that get a well balanced diet are much less likely to be sick than fish that are low on some vitamins or not eating what they need.

Ich Disease

Ich is one of the most common diseases found in Freshwater fish. The disease is caused by a parasite that affects the gills and fins of the body. Poor water conditions and stress are major reasons that can lead to the fish catching this disease. When a fish becomes infected with Ich, it tends to rub against hard objects such as decorations, rocks and the substrate.

Symptoms include white spots on the body, breathing difficulty and fish rubbing against hard surfaces. In comparison to other fish diseases, these symptoms make it easy to identify if your fish is infected.

A major concern is that this disease is highly contagious and can easily spread to other fish in your aquarium. If not treated early on, it can even cause respiratory issues.

Treatments include slightly increasing the water temperature, adding medication to the tank and performing a large water change. If you have a community fish tank then it is suggested to move the infected fish into a quarantine tank and then treat them.

Feeding Plecostomus

a pile of colorful fish flakes

Many pet stores sell Plecos as ‘algae eaters.’ While they do eat algae, this is not the only thing that they need to eat. Leaving them without food can lead to them starving or even death.

Depending upon the specific species they can feed on smaller fish, crustaceans and invertebrates. Some Pelcos may also prefer to feed on wood.

An ideal diet for most Pelcos should consist of algae and vegetables. They can feed algae rounds, wafers, earthworms or dry food.

Vegetables like zucchini, spinach, lettuce, cucumbers and shelled peas can also be fed to them. The vegetables should be peeled and finely chopped. Driftwood should also be kept in the tank because some Pelcos will feed on that.

They should be fed daily. If you are giving them raw vegetables, anchor them to the bottom of the tank or they may not see them floating above them.

Remember that Plecos are nocturnal and will mostly eat at night. While feeding them, keep in mind that they may not come out right away to eat their food. They are timid and like to eat food when no one is around.

Related Questions:

Are Plecos Good for Beginner Aquarium Owners?

If you can accommodate them in a spacious tank, then they can be a good fish for you, even if you are a beginner. Plecos are natural cleaners that reduce the maintenance needs for your tank. They will eat the algae and decaying organic matter in the tank. All you need to give them is a very large fish tank.