by Brett Harrington (Fogelhund)
The johanni has long been known in the Melanochromis genus, but is currently classified as a Pseudotropheus. This is a common cichlid in many Local Fish Stores, but is not a particularly good beginner cichlid due to its aggressive nature. If kept in tanks too small, or with inappropriate tank mates, it can dominate other fish, and has been known to harass them, often leading to deaths.
Should one decided to keep the johanni, it is recommended to keep at least four to six females for every male. Your tank should be no smaller than a four foot long, 75 gallon aquarium. The number of required females depends on what else you keep with johanni and their recommended tank size. If kept in a 6ft tank, with many other robust mbuna, you could get away with the minimum recommended numbers, but in smaller tanks you would want six females, or maybe even more, depending on how aggressive the individual male is.
Appropriate tank mates include; Metriaclima zebra types (callainos, estherae, chilumba..etc), Metriaclima lombardoi, Tropheops types, Ps. crabro (bumblebee cichlid), and Labeotropheus species.
Females and juveniles are yellow, while males will be dark blue, with light blue horizontal barring.
Pseudotropheus johanni grows to about 4" maximum in the wild, while 5" is more common in captivity and even larger specimens are known. The johanni is not a particularly demanding species outside of its aggression. If kept with the proper number of females, with plenty of cover provided for fish to hide, they can easily be maintained and bred. A pH of above 7.0 and temperatures of 76F-80F, along with good filtration, regular water changes and quality foods should see success in keeping these fish for many years.
In the wild these fish are known as having an omnivorous diet, picking through the aufwuchs (algae bio-cover), consuming both algae matter, as well as insect larvae, copepods and plankton when available. In the aquarium they will readily eat any high quality flake food, or pellets. One should be cautious to not feed mammalian proteins, such as beef heart or liver. Live or frozen foods rich in protein should be fed sparingly. Mysis shrimp can be fed in moderate quantities, and would be preferable to brine shrimp (frozen or fresh).
Unfortunately, this is a species that appears to have been hybridized a great deal in the hobby, resulting in many fishes with both horizontal and vertical barring markings. If you plan on breeding and raising Pseudotropheus johanni, please be very careful in choosing your breeding stock, so that quality, pure specimens will continue to be available for the aquarium hobby. In addition, be cautions in keeping them with species that they are more likely to hybridize with, such as Ps. interruptus, cyaneorhabdos, Ps. deep, or Ps. socolofi.