Rainbow krib

The kribensis or rainbow krib (Pelvicachromis pulcher) is a small, colourful cichlid native to the still and slow-moving waters of Nigeria and Cameroon in West Africa. In the wild it inhabits heavily vegetated shallow waters, with some populations even occurring in brackish conditions. First introduced to the aquarium hobby in the 1950s, the kribensis remains one of the most popular and widely kept cichlid species, valued for its manageable size, attractive colouration, and ease of breeding. The vast majority of specimens in the trade today are captive-bred and are notably more adaptable and less aggressive than wild fish.

Males of this species reach up to 10 cm (4 in) in length while females are smaller at around 7.5 cm (3 in), with males developing pointed dorsal, caudal, and anal fins. Females display a characteristic deep purple belly when in spawning condition, making sex determination straightforward. Kribs are monogamous cave spawners that form strong pair bonds and are often the first cichlid bred by newcomers to the hobby. A breeding pair will fiercely defend their chosen cave and territory, though their aggression is usually limited to the immediate vicinity of the spawning site.

In the aquarium, kribs should be kept as a pair in a tank of at least 80 L (21 gal) with plenty of hiding places formed by clay pots, driftwood roots, and rock caves. A sand or fine gravel substrate is appreciated as the fish excavate pits when breeding. They accept a wide variety of foods, with a quality cichlid pellet as staple supplemented by live and frozen offerings. Water temperature should be 24–27°C, pH 5.0–7.5, with soft to moderately hard water. Good tankmates include small characins, barbs, danios, rasboras, Corydoras, gouramis, and Loricariids.