Julidochromis Transcriptus

Cleveland Aquarium Society

an all-species aquarium society

Julidochromis Transcriptus

A Breeder's Report by Alan Robbins, CAS^©

Julies come from Lake Tanganyika, a lake 670 kilometers long by 80 kilometers wide. It is bordered on the north by Burundi, on the east by Tanzania, on the south by Zambia and on the west by "Democratic Republic of the Congo", formerly Zaire. Tanganyika's maximum depth of 1470 meters makes it the second deepest lake in the world, exceeded only by that of Lake Baikal.

The water in Lake Tanganyika is rich in dissolved salts, and has high carbonate hardness and total hardness. The carbonate hardness of the aquarium water should be kept at around 1 5 and the dGH values in the lake vary between 9 and 11. The pH-value should be at least above neutral. pH measurements in Lake Tanganyika showed values exceeding pH 9. The fishes from Lake Tanganyika do not cope well with soft and acidic water, but are often tolerant to slightly higher or lower values than those found in the lake.

The surface temperature varies from 23 C to 28 C, depending on the season. Deeper down the water temperature is slightly lower. Due to the even thermocline there is little exchange between the surface water and the sulfur-rich water on the bottom. Below 200 meters, the dissolved oxygen concentration is very low and higher forms of life can not be found below 250 meters (Coulter, 1967).

The Julidochromis genus consists of 5 species, some of which are known to have multiple color forms. J. transcriptus is the smallest species in the genus, with adult size under 7 cm., but has the characteristic torpedo shape and mottled brown and white patterns found in the genus.

I started with eight fry from one of our BAP auctions. They were ½ to ¾ inch long at the time. It is important to start with at least 6 fish to insure getting a pair. I put the Julies in a 29-gallon tank loaded with tuffa rock forming caves.The temperature was maintained at 78°, I fed them various flakes and frozen baby brine shrimp and they grew rapidly. I began to notice that certain individuals seemed to hide in the corners and plastered themselves along the glass walls. These "heater-huggers" were removed.Eventually one pair remained. They chose a cave and stayed in it most of the time. On a few occasions, usually late at night, I would notice unusual activity: shaking and trembling, but never found eggs or fry. During one water change, however, I noticed something very small moving away from the siphon. FRY! I was able to find only 3 of them.

Although I began feeding live baby brine shrimp when I discovered the fry; they seem to be able to survive on the microscopic life living on the tuffa rock until they are large enough to eat crushed up flakes.

I have discovered that transcriptus seem to be very intolerant of water changes. I do only small water changes, no more than 10% at a time because larger ones seem to stop them from breeding. They do best when there is a good bloom of algae covering the rocks and the glass, so I clean only the front glass and the fluorescent light stays on 24 hours a day. There are no other plants or fish in the Julie tank.Another interesting observation is that my pair produced batches of up to a dozen eggs every week. There are perhaps half that many size cohorts of juveniles in the tank. It is unusual to see such parental tolerance of older fry with the younger ones.

I found it nearly impossible to remove any of the fry from the tank without first removing the rocks. This is not only a big job, but also disturbs the breeding cycle.

Reference: Loiselle, P.V. The Cichlid Aquarium; The Tetra Press; 1985

Riehl, R. and Baensch, Aquarium Atlas; Tetra-Mergus;1991

Hans Joachim Herrmann; Aqua Net topic: the Cichlids of Lake Tanganyika on the Internet at: http://www.aquanet.de/english/topic/tanganyika/

Photo by Roger Doyle