Blue Phantom Pleco (Hemiancistrus sp. L128): Ultimate Care Guide

Like most plecos, the Blue Phantom Pleco is an armored fish that belongs to both the catfish and the pleco families. One of the main things that set the Blue Phantom Pleco apart from other pleco types is its unique blue coloring with white dots throughout its body.

Originating in Venezuela, the Blue Phantom Pleco has been known to live in the Rio Orinoco River. The best way to keep these fish happy is to replicate their natural habitat as closely as possible in your aquarium.

Blue Phantom Pleco is known to be highly active, but they are generally peaceful fish that will not cause conflict in the tank. They will be compatible with most other fish of similar size and temperament. Therefore, they are great candidates for a community tank with multiple different species. While they usually do not cause problems in the tank, they appreciate some hiding places that allow them to escape from the chaos occasionally.

Blue Phantom Pleco
Blue Phantom Pleco (Hemiancistrus sp. L128). Edited. Ericzerosept, CC BY-SA 3.0

Blue Phantom Pleco Care

Blue Phantom Plecos are not the hardiest fish, at least in comparison to other types of Plecos. They require good water quality, so regular water changes and monitoring of the water parameters are important. When the tank is neglected and the water conditions get degraded, it will cause stress to the fish.

Since Blue Phantom Pleco do not respond well to sudden changes in their environment, it is important that their tank is set up correctly. Being vulnerable to the consequences of a poorly cared tank, it doesn’t matter that there isn’t a specific disease targeting this species. Suppose they are weak and stressed enough due to less favorable water parameters. In that case, there’s a higher chance that any infections or illnesses due to the same shift in the quality of the water parameters will be able to work their way into your fish’s body.

Ideally, if you do everything right and monitor the water parameters, do regular water changes, and keep the fish well-fed, they can live for a long time. While five to eight years may not seem like a long time compared to other catfish species, that wide range leaves a lot up to the aquarist. There’s a sense of pressure applied here when you think about the fact that if you don’t care for your fish properly, you’re inevitably shortening its lifespan.

For a similar reason, it’s important to get your fish from a reputable place to know if the fish is sick, has been sick, has been exposed, how they were cared for, and if the care they did receive was appropriate to the specific species. This is another aspect of life where convenience may take the back seat while logic and reason are more important. If you are a serious aquarist, you know that this has to be taken seriously as there can be a number of things that go wrong when you first introduce a new fish, or even if you’re getting a fish that you’ve never cared for before.

Ensuring that all fish in the tank is in an environment that fits their designated specifications and proves to be fun and safe for them is important in predicting whether your tank will succeed.


Since they originate from Venezuela, it shouldn’t be too much of a surprise that the Blue Phantom Pleco prefers for their water to be moderately warm. If the tank’s temperature remains within the 70-78 degrees Fahrenheit range, the Blue Phantom Pleco should be content and capable of remaining healthy.

Water pH

The Blue Phantom Pleco prefers water with a pH that stays within the rather neutral range of 6.0-7.0. Unfortunately, this species is very sensitive to changes in the water parameters and can become quite stressed out and, in extreme cases, also quite ill.

Blue Phantom Pleco Size

The rate your Blue Phantom Pleco grows will help determine if you are taking good care of the fish. When they are healthy, they’re likely to grow larger than if they weren’t healthy and properly cared for.

The Blue Phantom Pleco can grow to approximately 7.5 inches long, but those are usually the larger specimen. Being that they are expected to grow to an average of about 7 inches, you should note that if your fish doesn’t reach that size, it may hint that it isn’t as healthy as it should be. If your fish truly is healthy, there’s a chance that they will surpass that estimated 7 inches.

Food & Diet

The Blue Phantom Pleco is an omnivorous fish and will be perfectly content with a diet that is vegetable-based, or a diet that is meat-based, leaving bloodworms, green plants, and tiny portions of brine shrimp as options for you to use to feed your pleco. Thankfully, their lack of dietary restrictions makes it easy to feed them.

Are Blue Phantom Pleco good algae eaters?

Blue Phantom Plecos are good algae eaters. This is an important fact about them because the number of algae present in your tank will help you determine how often you feed them with supplemental food. If they have enough algae in the tank to munch on as they please, you won’t have to add supplemental food as frequently. This may also vary depending on how many algae eaters you have in the tank.

Blue Phantom Pleco Lifespan

As is the case with most living things, fish included, the care Blue Phantom Plecos receive will affect how long you can expect them to live. Provided that your caretaking ensures that the fish stays well fed on a regular basis, and the water parameters are kept within their ideal range, you can expect your fish to live longer than if the opposite was the case.

This species also has a chance to live longer than they would in the wild, in captivity. You can expect your pleco to live for anywhere between five and eight years, again, depending on the quality of the care that you provide and that they receive.

Blue Phantom Pleco Tank Size

Taking the size that these fish will grow to be into consideration, tank size does matter. Due to their size and high activity level, these fish need larger tanks. 20-gallon tanks seem to be sufficient for a Blue Phantom Pleco. Still, suppose you were looking to have multiple. In that case, it’s important to consider overcrowding and territorial behaviors and consider getting a larger tank before adding more of this species.

At the absolute minimum for an active fish of this size, there should be a designated 10 gallons per fish. However, each fish would have 25-50 gallons in a perfect world.

Blue Phantom Pleco Tank Setup

Due to their natural habitat being in a body of water that frequently experiences turbulence, the Blue Phantom Pleco enjoys it when their tank has a current. They are accustomed to environments that are comparable to a stream. They also prefer well-oxygenated water, which can be achieved by purchasing an air pump if you don’t already have one in the tank.

How to set up a tank for Blue Phantom Plecos

As with most fish, the way to ensure they are happy with their current living situation is to do your best to replicate their habitat in the wild. In this case, it’s important to know what the fish needs and prefers in order to be happy.

The Blue Phantom Pleco is quite active and needs a decent amount of space in the tank that it will be able to navigate as they swim around. They are also huge fans of decorations in the tank because they will be provided places to hide when they choose to keep to themselves.

Plecos, in general, prefer a smooth substrate in their habitat, such as fine sand, as there is less of a chance of them getting hurt or being uncomfortable, and the Blue Phantom Pleco is no different. If you were to use a rough and potentially sharp substrate in the tank, there’s a chance that the pleco will hurt itself during its search for food.

These plecos do not need a lot of wood in their tank and would be content with a discreet presence of driftwood and twigs. While some may think that placing more wood in the tank would be good for these fish to hide behind or under, there is also the option to use the tank’s vertical space.

Being that these fish are scavengers, it could be problematic if most of the bottom of the tank is full of obstacles that keep the plecos from being as active as they’d like or searching for food. Having taller rocks and caves available as hiding places for the pleco will be beneficial because the real estate on the bottom of the tank won’t be taken up as much.

Plants might be a good addition to the tank as it would make the Pleco feel more at home, but any aquarist should be made aware that there’s a chance that this species will uproot plants and occasionally snack on them. If you can look beyond plants getting some damage, the odds are that you will have a happy fish. Having green plants, they can munch on whenever they please similar to monitoring your tank’s algae population. If there is a significant food source in the tank, you won’t have to feed your Pleco as often.

Do they need wood?

Generally speaking, these fish do not need excessive wood in the tank. That being said, they are fond of having places to hide for extended periods of time.

Will Blue Phantom Plecos destroy plants?

While it isn’t necessary for Blue Phantom Plecos to have live plants in their tank, and there is a risk that they will destroy the plants, it may be worth adding them to the environment to help make the tank feel authentically like their natural habitat.

The Blue Phantom Pleco is peaceful for the most part, but there is no guarantee that they will leave the live plants alone as they eat almost anything, including green plants. Some sources have even reported that they are known to uproot and damage plants.

Blue Phantom Pleco Breeding

This species, in particular is not known for being easy to breed. We know that it isn’t impossible to breed these fish, as there have been a few reports of successful attempts, but the underwhelming number of instances proves that it’s difficult to achieve.

If you’re trying to figure out whether or not your Blue Phantom Pleco is pregnant, keep an eye on her behaviors to see if there is anything that may be out of the ordinary. If she is more still than usual and resting in cool and calm areas in the tank, and her belly starts to look bigger, there’s a good chance that you have a pregnant pleco on your hands.

Blue Phantom Pleco Male or Female

Usually, a male Blue Phantom Pleco is a thinner and longer version of the female. Females are also known to have more of a rounded belly, comparable to other fish.

Blue Phantom Pleco Disease

While there are no diseases that the Blue Phantom Pleco is particularly susceptible to getting, all fish are vulnerable when it comes to common fish illnesses such as ich, dropsy, fin rot, and fungus. These diseases can be prevented by ensuring the quality of the water conditions is acceptable. Even the hardiest of fish can fall ill due to a decrease in the quality of their water conditions.

Blue Phantom Pleco Tank Mates

Generally speaking, the Blue Phantom Pleco seems to be tolerant of tank mates that are of a similar size. They also don’t seem to have much of a problem coexisting in a space with various other species. It’s best to ensure your pleco has somewhere to hide when the other fish suddenly become too much to handle. It’s common for them to take a break and hide for a while.

In order to avoid drawing out the potentially aggressive side of your fish, it’s best to avoid putting them in the same tank as another Blue Phantom Pleco. If you were to pair these fish, they would start to exhibit defensive and aggressive behaviors that could become problematic.

Blue Phantom Pleco and Betta

Being that the Blue Phantom Pleco generally does well with other species and in community tanks, these two would most likely be compatible in a tank. Although they both have the ability to become aggressive and territorial, the fact that they typically remain at different levels in the tank means that they are not likely to cross paths enough to irritate one another.

Blue Phantom Pleco and Goldfish

With their peaceful nature and ability to peacefully coexist with other species, it’s likely that Goldfish will be a compatible tank mate for this pleco. Their similar size also helps encourage the notion that they can coexist.

Blue Phantom Pleco and Bristlenose Pleco

Although some plecos should be kept separately due to their ability to get aggressive, the Blue Phantom Pleco and the Bristlenose Pleco are compatible as tank mates. Rubber Lip Plecos are another viable option as a tank mate for the Blue Phantom Pleco.

Blue Phantom Pleco and Shrimp

This pairing does not appear ideal when you look at the fact that some Blue Phantom Plecos are fed brine shrimp. However, since the shrimp will not be present in the form of small pieces, there’s a chance that the two species will be able to keep to themselves and essentially ignore the other’s presence.

Blue Phantom Pleco and Corydoras

Yes, these two would be compatible as tank mates because they are both rather docile and keep to themselves. Although the Corydoras are small, it is unlikely that they will cause any trouble for the Blue Phantom Pleco.

Blue Phantom Pleco and Discus

It is likely that these two will also be compatible as tank mates. The wide variety of fish that would be able to coexist with the Blue Phantom Pleco peacefully is thanks to the fact that any aggression that they are capable of displaying is usually reserved for the same species and matters of possession and territorial behaviors.

Blue Phantom Pleco and Cichlids

Blue Phantom Plecos and small cichlids are compatible as tank mates, but if there is a breeding group within the tank’s cichlid population, there is a chance that the pleco will eat the fry. One of the most important factors in ensuring that two species will be compatible tank mates in this situation is that they are around the same size.

Where can I find Blue Phantom Plecos for sale?

Although you may be able to find them elsewhere, it is recommended that you purchase your Blue Phantom Pleco from an aquarium supplies store with a good reputation in order to decrease the chance that your fish may be carrying a disease.

As a side note, buying your fish from reputable locations is always recommended rather than settling for your local pet store, as there is a clear difference in the quality that the fish receive.

If you don’t have access to a reputable location with aquarium supplies and life, isolating your new fish in a quarantine tank is highly encouraged. The reason for doing this is to ensure that the new fish do not bring harmful diseases or bacteria into your tank. When introducing new fish to your preexisting tank, if they’re carrying illnesses, there’s a relatively good chance that they will contaminate the rest of your tank.

As harsh as it may be, replacing a fish that succumbed to its illnesses is easier than treating or replacing an entire preexisting aquarium setup. If you’re just starting a tank and it doesn’t yet have any fish in it, the quarantine tank step is unnecessary.

Blue Phantom Pleco Price

Blue Phantom Plecos are on the more expensive side when compared to other plecos. As with all fish, the price varies within a generally specified range depending on the size of the fish at the time of purchase. The price can fall below the price range of $25 to $75.


Overall, the Blue Phantom Pleco could be a great addition to most tanks, and its rather average preferences regarding pH and water temperature make for an easy transition. If you already have a preexisting tank, and your water, temperature, etc., are already up to the standards of this Pleco, the lack of environmental changes will hopefully leave the fish that were already in the tank unphased and relaxed.

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