The answer is males can reach a length of 4 inches (10 cm), while the female usually stays around 3 inches (8 cm). 

 

Affectionately referred to simply as “krib” among cichlid hobbyists, this West African cichlid is called kribensis its species name, or P. kribensis. The modern accepted scientific name is Pelvicachromis pulcher, which translated means “beautiful belly fish". 

 

Pelvicachromis pulcher is a freshwater fish of the cichlid family, endemic to Nigeria and Cameroon.It is very popular amongst aquarium hobbyists, and is most commonly sold under the name kribensis, although it has other common names, including various derivatives and color morphs of the kribensis: krib, common krib, red krib, super-red krib and rainbow krib, along with rainbow cichlid and purple cichlid.

 

Pelvicachromis pulcher was originally described as Pelmatochromis pulcher by George Boulenger in 1901. Subsequently, a number of junior synonyms (Pelmatochromis aureocephalus, Pelmatochromis camerunensis) and misidentifications (Pelmatochromis kribensis, Pelmatochromis subocellatus var. kribensis and Pelmatochromis pulcher var. kribensis) were brought into use.