I did a fishbase search and found one of the alternate spellings. Here's the data I found: The fact that is is found in both the lake and a tributary leads me to believe that the water conditions would be more like Lake Victoria and not really critical as long as you stay away from extremes. (Softer than malawi, harder than Amazon)
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Sarotherodon lohbergeri (Holly, 1930)
Family: Cichlidae (Cichlids) , subfamily: Pseudocrenilabrinae
Order: Perciformes (perch-likes)
Class: Actinopterygii (ray-finned fishes)
FishBase name: Keppi
Max. size: 10.6 cm SL (male/unsexed; Ref. 4999)
Environment: demersal; freshwater
Climate: tropical; 25 - 27°C; 5°N - 4°N
Distribution: endemic to Lake Barombi Mbo and Kumba stream (tributary of the outlet of Barombi Mbo, west Cameroon).
Biology: Usually forms schools at the surface. Feeds mainly on epiphytic and epilithic filamentous algae, and the diatoms, rhizopods, rotifers and organic debris found among them. The adults feed by opening their mouths very wide and applying them to the surface of the rock as though sucking the material in (Ref. 2).
Red List Status: Critically Endangered, see IUCN Red List (B1+2c),