The Malawi Eyebiter Dimidiochromis compressiceps is a fabulous looking, predatory cichlid from Africa. This fish makes a truly an impressive show piece with its dynamic blue metallic coloring and very unique shape. It it is extremely compressed laterally, making it possibly the most flattened cichlid in Lake Malawi. It reaches up to 10 inches (25 cm) in length and has a forward projecting, toothed lower jaw. This thin body shape allowing it to move with great bursts of speed, coupled with its strong jaws, make it a lethal predator of small fish.

This is a very interesting fish to keep and definitely adds diversity to the appropriately stocked Malawi cichlid tank. The unique physical aspects of the Malawi Eyebiter makes it a favorite to some cichlid admirers. Some of its common names are derived from its shape, such as the Compressiceps and Haplochromis Compressiceps.

It is also called the Eyebiter. It is said to have earned this name due to an infrequent behavior of plucking the eyes out if tankmates. It is said to have been observed by native fishermen to bite the eyes out of other fish. However being an “eyebiter” is an action that will probably not be seen in captivity as long as they are well fed. This action is generally used toward smaller Mbunas it they end up in the same aquarium, but most often it is not a common habit.

In nature they don’t occupy the same types of habitats as the smaller rock-dwelling Mbunas. Rather these fish dwell in shallow waters that have both open areas and lots of vegetation.They feed mostly on juveniles of other open water swimmers like the Utaka cichlids and other shoaling youths, but sometimes the smaller Mbunas get snacked on as well. They are natural hunters so be careful with tank mates.

These fish are best kept by intermediate and experienced cichlid keepers. They are moderately difficult to keep due to the fact they need very large systems and very clean water. They also need a lot of hideouts. Bright tanks without plants will cause them to stress, leading to illness. Using denser bunches of real or fake plants in several areas of the tank will help to keep stress levels to a minimum.

These cichlids are highly predatory and will kill any fish smaller than themselves. Yet although they are predatory, they are only moderately aggressive. They do fine with other fish as long as the tankmates are the same size or larger and not overly aggressive. They should not be kept with any Mbunas or other smaller cichlids. They will generally attack and kill the smaller Mbunas, but they can be kept with larger plain colored Peacock cichlids without incident.

The Eyebiter is best kept in groups of one male and several females. They will attack and kill any other males of the same species unless the tank has hundreds of gallons. They will eat well and are only a threat to fish smaller than themselves. No fry from any other species will make it to adulthood with a Malawi Eyebiter in the tank.

Scientific Classification

Kingdom:Animalia
Phylum:Chordata
Class:Actinopterygii
Order:Perciformes
Family:Cichlidae
Genus:Dimidiochromis
Species:compressiceps

Malawi Eyebiter – Quick Aquarium Care

Aquarist Experience Level:Intermediate
Aquarium Hardiness:Moderately hardy
Minimum Tank Size:125 gal (473 L)
Size of fish – inches9.8 inches (24.99 cm)
Temperament:Semi-aggressive
Temperature:73.0 to 86.0° F (22.8 to 30.0&deg C)
 

Habitat: Distribution / Background

The Malawi Eyebiter Dimidiochromis compressiceps was described by Boulenger in 1908. It occurs in the Africa rift lake area and are found in many areas of Lake Malawi, the upper Shire River, Lake Malombe, and Mozambique. This species is listed on the IUCN Red List as Lease Concern (LC). It is endemic to Lake Malawi and these other waterways but is very widespread with no recognized threats at present. Other common names it is known by are Compressiceps, Haplochromis Compressiceps, and Eyebiter.

They are found in shallow waters within open areas above sandy substrates that have patches of Vallisneria and other vegetation, and sometimes in rocky areas. These areas are calm waters, virtually without any waves. They prey on small fish, especially shoaling species and juvenile Utaka and smaller Mbuna.

  • Scientific Name: Dimidiochromis compressiceps
  • Social Grouping: Solitary – It is mostly a solitary predator in nature.
  • IUCN Red List: LC – Least Concern

Description

Malawi Eyebiter is compressed, thin, yet deep-bodied, making it adept to very quick bursts of speed to catch its prey. It has been observed by native fishermen to bite the eyes of other fish and its having a forward projecting, toothed lower jaw helps with this. It can grow up to 10 inches (25 cm) in length, and will sometimes get larger in the aquarium. Lake Malawi fish live an average of 7 to 10 years.

The male is an almost metallic blue and sometimes green coloring, with an orange anal fin that has the typical egg pattern. The females are basically silver and the juveniles are light in color. All Haplochromis Compressiceps have a dark horizontal line down the middle of the body, extending from behind the eye to the base of the tail fin.

All cichlids share a common feature that some saltwater fish such as wrasses and parrotfish have and that is a well-developed pharyngeal set of teeth that are in the throat, along with their regular teeth. Cichlids have spiny rays in the back parts of the anal, dorsal, pectoral, and pelvic fins to help discourage predators. The front part of these fins are soft and perfect for precise positions and effortless movements in the water as opposed to fast swimming.

Cichlids have one nostril on each side while other fish have 2 sets. To sense “smells” in the water, they suck water in and expel the water right back out after being “sampled” for a short or longer time, depending on how much the cichlid needs to “smell” the water. This feature is shared by saltwater damselfish and cichlids are thought to be closely related.

  • Size of fish – inches: 9.8 inches (24.99 cm) – These fish grow to a length of 10″ (25 cm) in the wild, and sometimes larger in home aquaria.
  • Lifespan: 7 years – They have a lifespan of 7 to 10 years with proper care.

Fish Keeping Difficulty

This is a great fish for both the intermediate and experienced cichlid keeper. It needs a good sized aquarium and the aquarists must be willing to do frequent water changes and provide appropriate tank mates. Although it is a fierce predator that will kill any fish smaller than itself, it is one of the more peaceful cichlids with tankmates of the same size or larger. In the proper setup with the appropriate diet, it will readily adapt and is fairly easy to breed.

  • Aquarium Hardiness: Moderately hardy
  • Aquarist Experience Level: Intermediate

Foods and Feeding

The Malawi Eyebiter is an omnivore / piscivore with a large portion of their diet being small bony fish. They will kill and eat any fish that is smaller, and 1/2 its size for sure. It is not necessary to feed live feeder fish, which as with any cichlid will heighten aggression. They may be fed silversides, lancefish, prawns, cockle, mussel and other shellfish, shrimp, and some green veggies.

Vary their diet and they will reward you with beautiful coloring. They do need some vegetable matter to help prevent Malawi bloat. The babies can be fed mosquito larvae (blood worms), but need larger foods as they grow. They can also be given high quality protein based frozen cichlid food or pellets. A good diet along with vitamins will keep your Malawi Eyebiter in peek condition. Some cichlids cannot eat beefheart, so keep this in mind when housing these with the Malawi Eyebiter.

It is always better to feed them small amounts several times a day instead of one large feeding. This keeps the water quality higher for a longer period of time. Of course, all fish benefit from added vitamins and supplements to their foods

  • Diet Type: Omnivore – This fish is primarily a predatory piscivore, but it will eat some vegetable foods on occasion too.
  • Flake Food: No
  • Tablet / Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet
  • Vegetable Food: Some of Diet
  • Meaty Food: Most of Diet
  • Feeding Frequency: Daily – Offer several small feedings a day, what they can eat in about 3 minutes or less, rather than a single large feeding.

Aquarium Care

Malawi Cichlids will deteriorate under poor water conditions. As these are messy fish, do water changes of 20 to 50% a week depending on bio load. Malawi bloat is a typical disease especially if their dietary needs are not met with quality foods.

  • Water Changes: Weekly – Water changes of 20-50% weekly are suggested, depending on the bio load.

Aquarium Setup

The streams that flow into Lake Malawi have a high mineral content. This along with evaporation has resulted in alkaline water that is highly mineralized. Lake Malawi is known for its clarity and stability as far as pH and other water chemistries. It is easy to see why it is important to watch tank parameters with all Lake Malawi fish.

Rift lake cichlids need hard alkaline water but are not found in brackish waters. Salt is sometimes used as a buffering agent to increase the water’s carbonate hardness. This cichlid has some salt tolerance so can be kept in slightly brackish water conditions. However it not suited to a full brackish water tank. It can tolerate a salinity that is about 10% of a normal saltwater tank, a specific gravity of less than 1.0002.

A minimum 125 gallon tank will be needed for a solitary fish or a small harem. They need a tank large enough for their quick bursts of speed.  A larger tank will be needed if kept with other cichlids. They do fine in either freshwater or brackish freshwater but need good water movement along with very strong and efficient filtration. They can tolerate any ph above neutral, but a ph level of 8 is best. They enjoy a sand substrate or fine gravel. Sand used for saltwater fish or freshwater can be used, and can help keep the PH up. Crushed coral or aragonite sand can also increase the water’s carbonate hardness, and tend to dissolves easier than salts. Keeping a higher pH however, means that ammonia is more lethal, so regular water changes are a must for these fish.

Provide open swimming areas in the middle and bottom areas of the aquarium to mimic their natural environment. Bunches of live or artificial plants that reach to the surface will help reduce stress, as will hiding areas in the rock work. Live plants such as Vallisneria work well to imitate their natural habitat. These fish are not big diggers, and for the most part will not bother them. You will need to watch PH levels since decaying plants can lower the PH. The Malawi Eyebiter will use large, flat rocks to spawn.

  • Minimum Tank Size: 125 gal (473 L) – A minimum 125 gallon tank will be needed for a single fish or a small harem, a larger tank if kept with other cichlids.
  • Suitable for Nano Tank: No
  • Substrate Type: Sand/Gravel Mix
  • Lighting Needs: Low – subdued lighting
  • Temperature: 73.0 to 86.0° F (22.8 to 30.0&deg C)
  • Range ph: 7.7-8.6
  • Hardness Range: 6 – 10 dGH
  • Brackish: Sometimes – Salt is not found in their natural environment, but they do have a slight tolerance, keep levels below 10% – a specific gravity of less than 1.0002.
  • Water Movement: Moderate
  • Water Region: Middle – These fish will swim in the middle and bottom areas of the aquarium.

Social Behaviors

This fish is not considered to be a community fish. It is a predator but only moderately aggressive. As long as the tankmates are the same size or larger and not overly aggressive, they should be fine with this cichlid. However the Malawi Eyebiter is not friendly with Mbuna and will generally attack and kill the smaller Mbuna cichlids. They can be kept with larger Peacock cichlids without incident.

The Malawi Eyebiter is best kept in groups of one male and several females. They will attack and kill any other males of the same species in the tank unless the tank is hundreds of gallons. Do not put this fish with smaller cichlids. They are natural hunters and will attack anything small enough to eat.

  • Temperament: Semi-aggressive – They are natural hunters and will attack anything small enough to eat.
  • Compatible with:
    • Same species – conspecifics: Yes – They are best kept in groups of 1 male with several females. The male will attack and kill any other males of the same species in the tank unless the tank is hundreds of gallons.
    • Peaceful fish (): Threat
    • Semi-Aggressive (): Safe
    • Aggressive (): Monitor
    • Large Semi-Aggressive (): Safe
    • Large Aggressive, Predatory (): Threat
    • Monitor
    • Shrimps, Crabs, Snails: Threat – is aggressive
    • Plants: Monitor

Sexual differences

Males are colorful and typically larger. Females are smaller and mostly silver in color.

Breeding / Reproduction

The Malawi Eyebiter is a mouth-brooder that forms a matriarchal family, and it has been bred in captivity. Group one male with several females since the males can be quite aggressive towards the females during spawning time. They like a flat stone or slate to lay their eggs. Make sure this breeding site is not near a strong water flow since the eggs are externally fertilized.

Being a mouth-brooder, the female will pick up the eggs into her mouth for incubation. She will carry up to 250 eggs for about 21 to 28 days. It is evident she is brooding if she stops eating and has an enlarged mouth. When females are under stress or netted they have been known to spit out their eggs too soon. Some females like their spawning rock near the surface, but this is just a personal preference of an individual fish.If your Malawi Eyebiter is not spawning, you can try relocating the flat rock.

Some aquarists will keep the female separate, but prolonged separation from the main tank may affect her “social” status, resulting in fighting. You will have to test the personalities of your Malawi Eyebiters to determine the best course of action.

Once the fry have been released take them out of the tank as the male has no qualms about eating his children. Juveniles will eat mosquito larvae and brine shrimp until they get a little larger. Crushed spirulina for their veggie needs is suggested once or twice a week. See the description of how cichlids breed in: Breeding Freshwater Fish: Cichlids.

  • Ease of Breeding: Easy

Fish Diseases

The Compressiceps are susceptible to typical fish ailments, especially if water is stale and of poor quality and oxygenation. Malawi bloat is a typical disease especially if their dietary needs are not met with quality foods. One common problem is Ich. It can be treated with the elevation of the tank temperature to 86° F (30° C) for 3 days. If that does not cure the Ich, then the fish needs to be treated with copper (remove any water conditioners). Several copper based fish medications are available for Ich. Copper use must be kept within the proper levels, so be sure to follow the manufacturers suggestions. A copper test also can be used to keep the proper levels. You can also combine increasing the temperature with an Ich medication treatment.

As with most fish they are susceptible to skin flukes and other parasitic infestations (protozoa, worms, etc.), fungal infections, and bacterial infections. It is recommended to read up on the common tank diseases. Knowing the signs and catching and treating them early makes a huge difference. For information about freshwater fish diseases and illnesses, see Aquarium Fish Diseases and Treatments.

Availability

The Malawi Eyebiter, also called Compressiceps, is often found online for a moderate price. Prices do vary depending on whether they are male, female, or juvenile. They are usually found in fish stores, though may be special ordered if you are willing to wait for them if they are out of season.

Sources

 

Featured Image Credit: chonlasub woravichan, Shutterstock