Melanochromis johanni

Classification

Cichlidae

Distribution

Endemic to Lake Malawi. It is found around Masinje Rocks and Cape Ngombo.

Habitat

It is usually found in relatively shallow water in rocky coastal areas.

Maximum Standard Length

Males to 4.8″ (12cm), females to 4″ (10cm).

Aquarium SizeTop ↑

36″ x 18″ x 15″ (90cm x 45cm x 37.5cm) – 160 litres.

Maintenance

Much of the aquarium should contain piles of rocks arranged to form caves with small areas of open water between. A sandy substrate is best and the water should be well oxygenated. Plants should not be used as they will be eaten.

Water Conditions

Temperature: 73-81°F (23-27°C)

pH: 7.6-8.8

Hardness: 10-25°H

Diet

M. johanni will accept most foods offered but vegetable matter in the form of spirulina flakes, blanched spinach etc. should form a large proportion of the diet. This can be supplemented with live and frozen varieties.

Behaviour and CompatibilityTop ↑

Quite aggressive but it is not as pronounced in this species as with most other Melanochromis species. It can be housed successfully with similarly-sized mbuna and can even be kept with similarly sized peaceful species such as Aulonocara or Neolamprologus. If it is kept in a mbuna community the tank should be overcrowded to reduce aggression and territory formation. Male fish are aggressive and territorial towards conspecifics and a large tank is required if more than one male is to be kept. Several females should be kept per male.

Sexual Dimorphism

This species exhibits very clear sexual dimorphism. Male fish are blue-black with bright blue striping while females are orange in colour. Males also tend to be slightly larger than females.

Reproduction

Relatively easy. Maternal mouthbrooder. It should be spawned in a species tank in a harem of one male and at least 3 females. A 36″ aquarium is a good size and this should be furnished as suggested above, along with some flat stones and areas of open substrate to act as potential spawning sites. The pH should be around 8.2-8.5 and the temperature 77-80°F. The fish should be conditioned with plenty of live, frozen and vegetable foods.

The male fish will clean and then display around his chosen spawning site, showing intense colour, and attempt to entice females to mate with him. He can be quite aggressive in his pursuits and it is in order to dissipate this aggression that this species should be spawned in a harem. When a female is willing, she will approach the spawning site and lay her eggs there, after which she immediately picks them up in her mouth. The male fish has egg-shaped spots on his anal and the female is attracted to these. When she tries to add them to the brood in her mouth she actually recieves sperm from the male, thus fertilising the eggs.

The female may carry the eggs for around 3 weeks before releasing the free swimming fry. She will not eat during this period and can be easily spotted by her distended mouth. If a female is overly stressed she may spit out the brood prematurely or eat them, so care must be taken if you decide to move the fish in order to avoid fry predation. It is also worth noting that if a female is away from the colony for too long she may lose her position in the pecking order of the group. We recommend waiting as long as possible before moving a female unless she is being harassed. Some breeders artificially strip the fry from the mother’s mouth at the 2 week stage and raise them from that point as this usually results in a larger number of fry.
The fry are large enough to take brine shrimp nauplii from the time of release. The female will continue to guard the brood for the first week or so following their release, taking them into her mouth when she feels threatened.

NotesTop ↑

This species can be distinguished from the similar M. cyaneorhabdos by the overall black colouration of dominant males, as opposed to the more blueish patterning of cyaneorhabdos. It is sometimes sold as “electric blue johanni”. Do not keep it with other Melanochromis species as they may hybridise.