Freshwater Fish

Hemiancistrus L128 (Blue Phantom Pleco)- Care Guide

When it comes to functional freshwater fish, one of the largest and most popular groups in the aquarium trade is the algae-eating catfish known as Plecostomus. If you’re looking for a rare and unique bottom dweller for your medium-sized community aquarium, consider getting a beautiful Blue Phantom pleco for your tank!

Quick Facts on Blue Phantom Plecostomus

  • Common name (species): Plecostomus ghost blue (species Hemiancistrus L128)
  • Family: Loricariidae
  • Origin: Orinoco River, Venezuela
  • Care level: Easy
  • Average size: 7 inches long
  • Diet: Omnivore
  • Feeding: Offer daily meals of sinking algae wafers, spirulina granules, and freshly blanched greens, with a few weekly treats of brine shrimp, bloodworms, or other live treats.
  • Activity: Night; more active at night and prefers to hide during the day
  • Temperament: Peaceful and mild
  • Tank Level: Bottom Dweller
  • Minimum tank size: 50 gallons
  • Temperature Range: 77 to 86°F
  • Water hardness: 2 to 12 KH
  • pH range: 6.0 to 7.0
  • Filtration/Flow Rate: Lives naturally in very clean, highly oxygenated water at high/moderate flow rate, but tolerates gentle currents as long as filtration and aeration are adequate.
  • Brood: Egg layer; male fish protect the eggs until hatching. It rarely breeds naturally in captivity.
  • Compatibility: Works well in most peaceful and semi-aggressive communities. Excellent choice for Amazon themed tanks with small Cichlids, Characins and Silver Dollars
  • Is it ok for planted tanks? Yes, but it can consume or uproot plants.

Natural history of the blue ghost Plecostomus

Blue ghost plecos are members of the large armored suckermouth catfish family. They are a medium-sized, peaceful scavenger that does well in community aquariums 50 gallons and up. Rarely bred in captivity, Blue Phantoms are scientifically classified as an unknown species in the genus Hemiancistrus.

To avoid confusion, aquarists use a system of L numbers to identify single varieties of Loricariidae catfish when the scientific names are absent or too broad (as with the clown plecos and their imitators):

  • Blue ghosts are identified and sold as L128 under this system.
  • They may be a southern variation or subspecies of the green ghost pleco (Hemiancistrus subviridis), identified as L200.
  • Blue ghosts are a rarer but widely available variety of pleco that often sell for a premium price, and it’s not uncommon to see them in the $50-150 range.


While largemouth catfish species are found across a wide range of Central and South America, Blue Ghost populations are only found in a limited and specific region. They are native to the Rio Orinoco in Venezuela, specifically the area downstream from Puerto Ayacucho:

  • They live in river rapids and hide under boulders and rocks during the day, feeding primarily on algae and plant material along with small insects, worms, and larvae.
  • They are tolerant of smooth water flows as long as their water is clean and well-oxygenated.

Appearance and size of the blue ghost

Ghosts have the typical pleco body shape, with a wide sucker mouth and flat head leading to a narrow body and upright dorsal fin. As burrowers, they also have strong, wide pectoral and abdominal fins. Blue Phantoms are a beautiful catfish with impressive markings:

  • They have a carbon black base color that can scratch into a deep navy under certain lighting conditions.
  • Its name comes from the small iridescent bluish spots on the body and fins.

Blue Phantoms are generally sold as juveniles when they are 3 to 5 inches in length, averaging 7 inches from snout to tail at maturity. Like the other species of armored catfish, these plecos do not have scales and are instead protected by heavy and thick plates.

Life expectancy

Plecos typically live for around a decade in captivity, but it depends on their environment. If you keep your tank in good shape and feed it a balanced diet, you can keep your Blue Phantom for 12-15 years!

behavior and temperament

Blue Ghosts are a gentle, shy, peaceful pleco that do very well in medium to large community aquariums. While they usually hide under rocks and decor during the day, they can be quite active scavengers once the lights fade. It’s fun to see them swimming in your filter outlets or bubble walls with a moonlight !

Like catfish, blue ghosts are opportunistic and try to eat anything they find. But unlike the giant and aggressive Common Pleco, they are not active hunters and usually leave schools alone. They are non-territorial, and you can keep them in groups or with other peaceful plecos like the Bristlenose.

How to care for your Blue Phantom pleco

Blue Phantoms are generally easy to care for, but are not as hardy as some plecos. It is best to allow them plenty of time to acclimate to you local water conditions in a quarantine tank before introducing them to your aquatic community.

Tank Configuration and Habitat Requirements

While wild ghosts typically live in waterways with strong currents, waterfalls, and rapids, captive fish will tolerate aquariums with gentle currents as long as their water is very clean and highly oxygenated.

aquarium size

Blue Phantoms are active bottom dwellers that need plenty of room to swim and poke around in the bottoms of your tank. They are ideal for tanks 50 gallons or larger, especially long style or rearing tanks. I recommend allowing an additional 25-50 gallons per Phantom to avoid stress.


The ideal substrate for a Blue Phantom tank recreates its natural environment and includes a mix of soft sand and smooth pebbles. Avoid using coarse aquarium gravel, which could damage the abdomen or fins. Aquatic soils can also work, but these plecos often foul them with mud.

Water and temperature parameters

Ghosts prefer warm, stable water temperatures between 77 and 86°F, so it’s best to use an aquarium heater. They prefer slightly soft water from 2 to 12 KH with a neutral pH of 6.0 to 7.0. Plecos get stressed when their conditions change suddenly and require extra time for acclimatization.

Filtration and aeration

While wild catfish prefer turbulent conditions, you don’t have to use a powerhead to make waves in your tank. As long as you have a good filtration system with replaceable filter media and maintain high oxygenation of the water with bubbler devices or air stones, Blue Phantoms can tolerate living in tanks with gentle currents.

I recommend using a sturdy canister or a pair of HOB filters, depending on the capacity of your aquarium and if you’re also using a powerhead. Dirty water and hypoxic or low oxygen conditions cause these fish a lot of stress and can significantly reduce their life expectancy.

Lights, Plants and Decorations

As nocturnal plecos, avoid bright areas of your tank during the day. They prefer to hide under rock piles or in cracks near your filter outlets. The ideal decoration for a ghost tank is tall piles of rocks and boulders. You can also include driftwood or branches, but these catfish don’t need a lot of wood. You can keep Phantoms in a planted aquarium, but they often uproot and damage live plants.


Blue Phantoms are not as hardy as other pleco species and get very stressed when kept in dirty water. As voracious eaters, they produce a lot of waste, so plan on doing at least monthly water changes and filter maintenance on your pleco tank.

Feeding Blue Phantom Plecos

While these scavenging catfish enjoy eating aquarium algae and cleaning up food debris left behind by other fish, you will still need to offer your plecos commercial diets and treats to balance their nutrition. It is best to feed Blue Phantom at night, when they are just coming out of hiding:

  • Offer a daily sinking meal of algae wafers and spirulina granules, with freshly blanched vegetable treats like cucumber, zucchini, and peas.
  • Several times a week you can feed a high protein treat such as live/frozen/dried brine shrimp, bloodworms, mosquito larvae or Daphnia eggs.

tank mates

These peaceful catfish do well in a variety of mixed communities, so the best tank mate really depends on the size and setup of your aquarium. If you want to keep other turbulence-loving fish in a tank with a powerhead, consider making an Amazon -themed tank with Silver Dollars and Flagtail Characins. You can keep Blue Phantoms with peaceful and semi-aggressive communities:

  • They are a viable option for tetra, hatchet or barb tanks like the Tiger, Tinfoil and Odessa.
  • They generally get along well with smaller cichlids, although they may eat any fry produced by a breeding group.
  • Avoid keeping them with large, aggressive fish like Oscars or Common Plecos.
  • They are also an ideal choice for aquariums with other friendly plecos such as Clown, Bristlenose, Candy Stripe, Sailfin, and Rubber Lip.


There are some reports of successful breeding in captivity, but most of these fish are taken from the wild and sold for the trade. Your plecos are unlikely to breed in an aquarium or even a pond without the use of artificial hormones, even if you have a mixed group.

health concerns

These plecos are usually healthy and don’t suffer from many common problems aside from the usual waterborne parasites and infections. But Blue Phantoms are not as hardy as other types of plecos and are susceptible to stress when their conditions change. Always allow your fish more time to acclimatize and don’t fall behind on your aquarium maintenance or water changes.

Blue Phantom Pleco Configuration: List of Products and Equipment

Let’s take a look at the list of supplies you’ll need to start a tank for your Blue Phantom Pleco! For a single Phantom Community Aquarium, you will need:

  • 50 gallon or larger aquarium with stand and cover/hood
  • Filtration system (canister, HOB or combo)
  • Airstone or bubbler device, air pump and plastic pipe
  • Heater
  • Sand and pebble substrate
  • Variety of boulders, large and small rocks, and driftwood décor
  • water conditioner
  • water test kit

To feed your blue ghosts, you will need:

  • Commercial sinking algae wafers and spirulina pellets
  • freshly blanched vegetables
  • Treated as live/frozen/dried brine shrimp, bloodworms, Daphnia larvae or eggs

Optional but often useful equipment for a pleco tank includes:

  • Powerhead or aquatic wave generator for turbulent aquariums
  • LED aquarium lights and/or moonlight
  • live plants


What do you think of the Blue Phantom? Sound like a good algae eater for your aquarium? We’d love to hear your thoughts on these awesome spotted plecos, so please share them below or have fun with our larger community of fish breeders on our social media pages.

Publicaciones relacionadas

Deja una respuesta

Tu dirección de correo electrónico no será publicada. Los campos obligatorios están marcados con *

Botón volver arriba