Blue Dolphin (Hap)
Cyrtocara moorii
A striking blue Lake Malawi Haplochromine cichlid famous for the pronounced nuchal hump (head bump) that develops in mature adults, resembling a dolphin. They are benthopelagic micro-predators that naturally follow digging fish in the wild to catch stirred-up morsels. While relatively peaceful for an African Cichlid, they grow very large and require extensive swimming space and hard, alkaline water.
Blue Dolphin (Hap) At a Glance
Blue Dolphin (Hap) Tank Requirements
Will Blue Dolphin (Hap) fit in your tank?
Care guides tell you what Blue Dolphin (Hap) needs, the next question is whether your tank can safely provide it. Test Blue Dolphin (Hap) against your tank size, maintenance needs, and the fish you already keep before you buy.
Blue Dolphin (Hap) Water Parameters
Blue Dolphin (Hap) Temperament & Compatibility
Blue Dolphin (Hap) Varieties
Each variety inherits the species defaults above. Only differences are highlighted.
Adult Male
Mature males develop a massive, iconic nuchal hump on the forehead and brilliant light blue coloration. Best kept as a single male with multiple females (harem) or in a carefully balanced all-male Hap/Peacock setup.
Differs in 3 traits from base species
Also known as: Show Male, Bull
Adult Female
Females are slightly smaller and generally lack the massive nuchal hump, though they retain the beautiful blue coloration of the species. Significantly more peaceful than males.
Differs in 2 traits from base species
Also known as: Female Hap
Juvenile (Grow-out)
Young Blue Dolphins are silvery-blue with dark blotchy spots and lack the head hump entirely. They grow quickly and will eventually require a 125+ gallon aquarium.
Differs in 5 traits from base species
Also known as: Baby, Unsexed
Blue Dolphin (Hap) Care Guide Summary
The Blue Dolphin (Hap), scientifically known as Cyrtocara moorii, belongs to the Cichlids - African family group. Adults reach a maximum size of approximately 25 cm and have a compressed body shape with a moderate growth rate. Classified as semi-aggressive, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.
To thrive, the Blue Dolphin (Hap) requires a freshwater only aquarium with a minimum volume of 475 litres and a tank length of at least 150 cm. Water temperature should be maintained between 24°C and 28°C, with a pH range of 7.5–8.6 and a general hardness of 10–25 dGH. A moderate water flow is preferred.
The Blue Dolphin (Hap) is a rewarding species to keep, provided its core environmental needs are met. This species is available in 3 varieties: Adult Male, Adult Female, and Juvenile (Grow-out). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.
Blue Dolphin (Hap) Habitat Setup
When setting up an aquarium for the Blue Dolphin (Hap), a moderate water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour and smooth gravel or rounded substrate to protect their sensitive barbels. Keepers should note that expect substrate disturbance, so lightweight décor should be secured.
Blue Dolphin (Hap) Compatibility Notes
Classified as semi-aggressive, the Blue Dolphin (Hap) is adaptable and can be kept singly or in a small group, offering flexibility when planning a community tank. When choosing tankmates, conspecific aggression can be intense, especially in smaller tanks and their energetic swimming style may stress more sedentary or timid species. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.
Who Blue Dolphin (Hap) Is Actually For
Blue Dolphin (Hap) is best for a fishkeeper who wants a species that can settle into a calmer community setup and can provide someone who understands its individual space requirements. It makes the most sense for a hobbyist who will actually build around its needs, especially sand.
The most common mistake is treating Blue Dolphin (Hap) like any other community fish and skipping the soft sand it needs to forage safely. Another frequent problem is forcing it into an over-busy community when it would do better with more room or more deliberate tankmate choices.
Blue Dolphin (Hap) Recommended Tank Sizes
Standard aquarium sizes that meet the minimum volume and length requirements for Blue Dolphin (Hap).
Frequently Asked Questions About Blue Dolphin (Hap)
How big does Blue Dolphin (Hap) get?
Blue Dolphin (Hap) (Cyrtocara moorii) typically reaches a maximum adult size of approximately 25 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Blue Dolphin (Hap) need?
A minimum aquarium volume of 475 litres and a tank length of at least 150 cm are recommended for Blue Dolphin (Hap). This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Blue Dolphin (Hap) need?
Blue Dolphin (Hap) thrives in freshwater only conditions with a temperature range of 24–28°C, a pH between 7.5 and 8.6, and a general hardness of 10–25 dGH. A moderate water flow is preferred.
Is Blue Dolphin (Hap) peaceful or aggressive?
Blue Dolphin (Hap) is classified as semi-aggressive with an aggression score of 5 out of 10. They can work in community setups but may clash with certain tankmates.
Can Blue Dolphin (Hap) live alone?
Yes, Blue Dolphin (Hap) can be kept singly or in a group. They are flexible and adapt well to both setups.
Does Blue Dolphin (Hap) have any special tank requirements?
Yes. Blue Dolphin (Hap) benefits from sand (sifters) and smooth gravel (sensitive barbels) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.
Useful setup supplies
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Guidarium Editorial Desk
Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.
- Last reviewed
- April 28, 2026
- Last updated
- April 28, 2026
- Issues or corrections?
- Contact the editorial team
Plants That Suit Blue Dolphin (Hap)
These plants pair well with Blue Dolphin (Hap) based on shared water preferences, layout fit, and how likely they are to hold up in the same aquarium.
Afzel's Anubias
Anubias afzelii
Anubias Barteri
Anubias barteri
Belinda's Buce
Bucephalandra belindae
Buce Motleyana
Bucephalandra motleyana
Christmas Moss
Vesicularia montagnei
Congo Anubias
Anubias heterophylla
Fish Similar to Blue Dolphin (Hap)
Taiwan Reef Cichlid
Protomelas sp. "Steveni Taiwan"
A striking Lake Malawi Haplochromis (Hap) known for the breathtaking color transformation of mature males. Originating from the Taiwan Reef area in Africa (despite the misleading name), they are active swimmers that require hard, alkaline water, a sandy substrate for digging, and plenty of rockwork. They are primarily herbivorous in the wild and prone to 'Malawi Bloat' if fed too much heavy protein; a diet rich in spirulina is required.
Buccochromis rhoadesii
Buccochromis rhoadesii
A massive, apex-predator Haplochromine cichlid endemic to Lake Malawi. They are open-water pursuit predators characterized by an immense mouth and a distinct diagonal stripe across the body. Due to their enormous adult size and strictly piscivorous nature, they require massive aquariums and can only be housed with similarly large, robust species. Any tank mate small enough to fit in their mouth will be eaten.
Red Empress
Protomelas taeniolatus
A stunning and relatively peaceful Lake Malawi Haplochromine cichlid. Males develop breathtaking red and blue coloration, while females remain a camouflaged silvery-brown. Though considered a 'gentle Hap' compared to Mbuna, they are still large, active African Cichlids that require hard, alkaline water, plenty of swimming space, and rockwork.
Electric Blue Hap
Sciaenochromis fryeri
The Electric Blue Hap is a striking Lake Malawi cichlid. In the wild, they are specialized piscivores that hunt the fry of other cichlids among the rocks. Due to extreme sexual dimorphism, mature males develop a brilliant metallic blue coloration, while females remain a drab silver-brown. They are best kept in a large, hard-water aquarium either as a single showpiece male in an 'all-male' Hap/Peacock display, or as a single male with a harem of multiple females.
Malawi Gar
Lichnochromis acuticeps
An elegant, predatory Haplochromine cichlid from Lake Malawi, named for its elongated, torpedo-shaped body and pointed snout. While it is a true piscivore that will hunt small fish, it is surprisingly peaceful toward other similarly sized cichlids. A fantastic centerpiece for a large 'Hap and Peacock' setup.
Sunset Hap
Dimidiochromis strigatus
A striking, large, open-water predator native to Lake Malawi. As its name implies, mature males develop a spectacular 'sunset' coloration with a blue head fading into a deep orange-red belly. They are pursuit/ambush predators and will readily consume any fish small enough to fit in their mouths (including small Mbuna). Best kept in an all-male Hap/Peacock display or in a harem (1 male to multiple females).