Dwarf Mbuna

Pseudotropheus demasoni

FreshwaterFish

Care at a glance

Temperature: 75–82°F (24–28°C)
pH: 7.5–8.5
Adult size: 3.9 in (10 cm)
Minimum tank: 53 gal (200 L)
Temperament: Aggressive
Social behavior: Social
Swim level: Middle
Difficulty: Difficult
Breeding: No record
Rarity: Rare
Origin: Lake Malawi
Family: Cichlidae

Overview

This is an aggressive, territorial fish best left to experienced keepers, and it needs around 200 liters or more. The usual trick is to keep a large group, a dozen or more, so no single fish gets singled out and bullied. They are grazers, so feed algae and spirulina-based foods rather than a meaty diet, which can cause bloat. Pair only with other tough mbuna, never with timid fish.

In the wild

Demasoni come from the rocky shores of Lake Malawi, around Pombo Rocks, living in the shallow zone among piled boulders and crevices. The lake is hard and alkaline with a high pH, well into the 8s. Match that with a big rockwork setup full of caves and passages, hard water, and a pH around 7.5 to 8.5. Open swimming lanes between the rock piles help spread out aggression.

Good to know

This is a mbuna cichlid in the family Cichlidae, reaching about 10 cm despite the dwarf label. It wears bold blue and black vertical bars, and the sexes look nearly identical. Like other Malawi cichlids it is a maternal mouthbrooder, with the female holding eggs and fry in her mouth. It needs warm water in the mid to high 20s C.

Did you know

Because demasoni attack their own kind so hard, keeping just two or three usually ends with the weaker ones killed. Crowding them in big numbers is actually the safer approach, since the constant aggression gets shared around instead of focused on one victim.