Plecostomus, or plecos, are a group of armored catfish that belong to the Loricariidae family.
They are by far the most popular catfish amongst fish keepers, and in total, there are well over 150 species.
The most in-demand member of this family is called the common pleco and can grow up to 24 inches long.
In this article, we will discuss the various species, care, tank mates, aquarium requirements, and much more.
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Plecostomus Facts & Overview
|Size:||Up to 24 inches|
|Minimum Tank Size:||30 gallons|
|Tank Setup:||Freshwater: driftwood and caves|
|Compatibility:||Limited due to size constraints|
The plecostomus catfish, or pleco for short, is a name used for the catfishes that belong to the Loricariidae family.
In total, there are more than 150 different species; ranging from small to large and peaceful to aggressive catfish.
You may have seen the naming system the includes the letters “L” or “LDA”, followed by a string of numbers, which is used to identify the various members of the Loricariidae family.
Many beginner fish keepers think that common pleco refers generally to the Loricariidae family, but it actually refers to a specific member of the family, the Hypostomus plecostomus.
The common pleco is the most popular freshwater catfish among fishkeeping enthusiasts, and is a type of armored catfish.
It is found in the freshwater streams and rivers of South America, can grow up to 24 inches in length and have a lifespan of 10-15 years.
Plecos are naturally nocturnal. This means during the daytime, you won’t see much activity.
In the daytime, plecos can appear timid, and you will likely find them hiding among the plants and caves inside your tank.
When they are active, you will notice that they are a bottom-dwelling fish and move slowly across the floor of the aquarium.
It’s important to note here that while they will eat some algae, their diet should not be made up of algae alone. Additionally, you should not expect your plecos to clean your tank.
Many pet stores advertise them as algae eaters, which is dangerous as they are omnivores and require other nutrition.
Plecos tend to use their suckermouth to attach themselves to the glass or rocks within the aquarium.
Plecos generally have a friendly temperament, and they do best in a tank on their own due to size constraints (read the tank mates section below for more).
Most plecos are brown in color. However, the colors of some species are dependent on their environment. Most plecos also have sand-colored spots or patterns.
They are referred to as “armored catfish” because they have large boney plates that cover their bodies.
Plecos are unique because of their mouthparts, which look like a suction cup and allow them to attach themselves to smooth surfaces in your tank. Their mouths also allow plecos to eat up some (but not all) of the algae on the sides of the tank.
In the wild, common plecos will grow to around 24 inches in length, but in an aquarium, they tend to only grow to around 15 inches. The sizes of other species of plecos will vary.
Like other members of the pleco family, common plecos have elongated bodies which are covered with four rows of bone plates. The bone plates are not present on their abdomen.
They have well developed dorsal, pectoral, and tail fins. The dorsal fin has one coarse ray and seven soft rays. The anal fin has one coarse ray and between 3-5 soft rays.
Plecos have large heads with small eyes that are high up on their heads.
Interestingly, plecos have membranes covering their eyes which allow them to control the amount of light their eyes are exposed to.
One of the most interesting things about this fish is its tail fin. Pleco tail fins are moon-shaped, with the bottom part being longer than the top.
Types of Plecos
There are more than 150 different species of plecos. However, not all of them should be kept in an aquarium.
Below is a list of the most popular plecos for aquariums:
- bristlenose pleco (Ancistrus sp.)
- gold nugget pleco (Baryancistrus sp.)
- zebra pleco (Hypancistrus zebra)
- clown pleco (Panaqolus maccus)
- sailfin pleco (Pterygoplichthys gibbiceps)
- snowball pleco (Hypancistrus inspector)
- royal pleco (Panaque nigrolineatus)
Habitat and Tank Requirements
Most plecos are native to South America. They can survive in a wide range of habitats, with the majority of them living in fast-flowing streams and rivers with a rocky substrate. However, some can also be found in brackish estuaries.
You should remember that each species is unique, and no two pleco species will require the exact same habitat or tank setup. For example, smaller plecos such as the otocinclus catfish can survive in a 10-gallon tank, whereas larger species like the bristlenose need a minimum of 25 gallons.
Common plecos are usually only 2-4 inches long when first bought, but they grow very large, very quickly. Therefore, they are only suitable for more advanced aquarists in tanks of at least 80 gallons. As the pleco grows, you’ll need at least a 150-gallon tank.
Like most plecos, the common pleco’s natural environment consists of shallow streams and rivers that flow through tropical forests. This water tends to be fast-moving and littered with driftwood and plants. Plecos can be found hiding amongst these logs and plants during the daytime.
In order to set up a suitable tank for a common pleco, you should make sure that you add plenty of hiding places, as they will sleep in these places during the daytime. You can create these hiding places by adding caves and hollowed logs. You can also use upturned flower pots.
Plecos also prefer a tank that is heavily planted. You should make sure these plants are hardy, because your plecos and other fish may like to nibble on them.
Faster growing plants such as java moss are ideal. You should also make sure they always have access to driftwood to nibble on.
This combination of dense debris and vegetation helps to make plecos feel safe and secure.
Plecos are fairly hardy fish, so the water parameters aren’t as critical to maintain when compared to other fish.
The most important thing is maintaining a strong water current and keeping it well-filtered. To keep the tank well-filtered, you should use good-quality canister filters.
As for the water parameters, you should aim to keep the water temperature between 72°F and 86°F, with pH levels between 6.5-7.5.
The most important aspect of the water conditions is to ensure you keep your water clean.
What Size Tank Do Plecos Need?
The common pleco requires a huge tank. Once they reach their adult size, they will need at least a 150-gallon tank.
As for other popular species here are their minimum tank sizes:
- bristlenose pleco (Ancistrus sp.): 25 gallons
- gold nugget pleco (Baryancistrus sp.): 50 gallons
- zebra pleco (Hypancistrus zebra): 30 gallons
- clown pleco (Panaqolus maccus): 30 gallons
- sailfin pleco (Pterygoplichthys gibbiceps): 125 gallons
- snowball pleco (Hypancistrus inspector): 30 gallons
- royal plecos (Panaque nigrolineatus): 125 gallons
Diet and Feeding
Plecos are often sold as algae eaters, which would indicate that they are herbivores and can survive solely on algae. However, most plecos are omnivores and will eat smaller fish, invertebrates, and crustaceans that they come into contact with at the bottom of the tank. While plecos won’t kill other fish for meat, they will scavenge dead or dying fish, making them opportunistic omnivores.
Certain varieties of plecos also feed on wood, so make sure you thoroughly research the exact species you are interested in to ensure you meet their dietary requirements.
Many people believe that the common pleco can live purely on algae. However, this is incorrect and will lead to unhealthy, malnourished fish.
The common pleco’s diet should consist of vegetables and algae, but also some meaty foods that contain protein. High-quality pellets can be used to form the basis of their diet.
You can also feed plecos lettuce, zucchini, spinach, shelled peas, and cucumbers.
For live foods, you can feed your plecos bloodworms, earthworms, crustaceans, and larvae. Worms are often the best choice for plecos because they sink, meaning they will still have a chance to eat in a community tank.
Plecos require lots of fiber, so feeding them a lot of vegetables helps them meet this requirement.
As plecos are nocturnal, you should try feeding them at night just before you turn the lights in the tank off.
Plecos are fairly peaceful and can be kept in community tanks. Some ideal tank mates include:
Additionally, make sure you don’t add any smaller tank mates that could fit inside your pleco’s mouth. Any fish that can fit in a plecos mouth may find itself getting eaten before long.
As your pleco ages, it will quickly outgrow other fish and should be kept in its own tank.
Can You Keep Plecos Together?
In theory, you can keep plecos together, but in practice, it’s near impossible due to their size constraints. Plecos just tend to get too big to be safely kept together.
If you want to keep two or more together, you will need at least a 300-gallon tank, making this unreasonable for all but the most experienced fishkeepers.
Unfortunately, not much is known about breeding plecos, and even less is known about breeding them in an aquarium. However, one thing we know is that it is very difficult to breed them in captivity.
Plecos are egg-layers, and in the wild they generally spawn in caves, laying large volumes of eggs on flat surfaces.
The male pleco will then guard the cave until the eggs have hatched. Pleco fry are known for being demanding eaters that require large amounts of protein.
Is a Pleco Right For Your Aquarium?
If you’re looking for a unique, but large, addition to your tank, a common pleco might be just the thing your tank needs.
They are easy to keep and don’t have any complex care needs, but due to their size and the size of the aquarium they need, plecos are unsuitable for all but the most experienced fishkeepers.
Because of the maintenance efforts and costs required to keep a pleco, make sure it’s the fish for you before you decide to get one.