Yes here are a few species which would do ok in a 30gal
Julidochromis ornatus Boulenger 1898, the Golden Julie. East Central Africa; a Lake Tanganyika endemic. To a little over three inches in length. Rock dweller. pH range: 8-9, dH 9-18, temp. 20-24 C. Many different color, marking variations have occurred in this species with successive captive generations.
Julidochromis marlieri Poll 1956. Africa; northwestern part of Lake Tanganyika. To five inches in length. Peaceful as far as Cichlids go. Hardy, undemanding species. Micro-feeders, not carnivores in the wild. pH 7-9, dH 8-14, temp. 22-25. Breeds in caves and crevices.
Julidochromis regani Poll 1942, the Convict Julie. East Central Africa; a Lake Tanganyika endemic. To a little over five inches in length. Lives openly over shallow sandy bottoms. pH range: 8.5-9.2, dH 8-14, temp. 22-25. A popular genus and species of easier going African Cichlids, that have become adapted to more "common" aquarium water quality conditions with successive captive generations.
NOTE with the 2 speices that grow to 5" you will only be able to keep acouple of them not mas may as the other smaller speices.
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