Pseudotropheus demasoni 208 liters (55 gallons) breeding tank. Fish and Photo by Mark Ludl.
Pseudotropheus demasoni is a relatively new addition to the available Mbuna species from Lake Malawi. They differ in a few ways from the other Pseudotropheus species commonly available to the hobbyist. First, they stay smaller than most other species, only reaching about 10 cm, which allows them to be kept in a smaller aquarium. Second, the males and females have identical color patterns, which is rare in Pseudotropheus sp.. Lastly, they seem to be a little more delicate than other species in their family (this may be a matter of opinion).
I purchased my first group of 6 P. demasoni about 1 1/2 years ago at a local aquarium store. They measured about 2.5 cm long, and were placed into a 55 gal. tank. I lost 2 fish due to aggression/ disease, and added 3 more about 6 months later from the same store. The group now consists of the dominant male, who measures about 6 cm T.L., 3 females, who measure between 4 and 5 cm, and 3 others of unknown sex, which measure between 3 and 4 cm. Other tank inhabitants are 4 Labidochromis Caeruleus yellow form, 6 Zebra Danios, and 4 "Pearly" Labidochromis (may be the white form of L. Caeruleus).
The group is kept in a standard 208 liters (55 gallon) aquarium. Lighting consists of 2 48" 40 watt fluorescent daylight tubes, as well as a 20" tube, which is set to turn on before and turn off after, the main lights to simulate dawn and dusk. The substrate is a dark colored coral sand mixed with some aragonite. Decorations consist of 75 to 100 locally collected smooth stones, ranging from softball to walnut size. This creates many caves and crevices for the fish to swim through and hide in (and makes it impossible to catch any fish!). There are also some Java Ferns in the tank, but they aren't doing very well. The tank is filtered by 2 Emperor 400 outside power filters. These filters each have two extra media containers that were filled with Aragonite to help buffer the water. The filters create a lot of water movement, which keeps the water well oxygenated and the fish happy. The tank is heated by a 200 watt submersible heater. 50% of the water is changed every 10 days with tap water treated with a water conditioner. The water parameters are as follows: temperature 78.0 F, P.H.: 7.8 to 8.0, and Hardness: ~200 ppm.
Like most Pseudotropheus sp., P. demasoni needs a low protein diet, and any protein they do get, should be of fish, not animal, origin. The main food for my group is a mix of 5 different spirulina flakes, which are fed once or twice a day. There is a good growth of algae on all of the decorations, and the fish always seem be scraping it off the rocks and tank walls. They are also sometimes treated to some frozen or live adult brine shrimp. I am often away on weekends, so they go 2 or 3 days without a feeding.
Sexing P. demasoni is somewhat difficult. There are some subtle differences, but they are not completely reliable. The males are usually larger and more brightly colored than the females, and have longer ventral fins (although this may just be a sign of being larger). The best way to sex them is to watch their behavior, but this doesn't always work either. My second largest P. demasoni, which I was convinced was a second male, turned out to be a female about six weeks ago. I came home from work on day and she was holding.
I have unfortunately not been able to see any courting or spawning behavior, but it usually occurs after a water change, or after they have been left alone for a few days (maybe they get bored!). Because of all of the rockwork in the tank and a lack of time, I do not remove the brooding females from the main tank. For this reason I have not raised a large number of fry, but a few usually survive in the main tank. The females will start to peck at food after about 3 weeks, and start to release about a week after that. They take a few days to release all the fry, looking for little nooks in the rockwork to release them into. One thing that surprised me was the territoriality of the females, especially when holding. Each one has their own territory centered around a cave, which they actively defend against the other females. The females have no problems recovering after release in the main tank.
The fry do not receive any special care, and a few always survive in the main tank. They eat small bits of food from the adults and algae from the rocks. Each fry seems to find a very small crevice that only he can fit into, and centers his territory around that. They then become bolder and bolder as they get older and larger. Right now, the tank contains three 1 cm long juveniles, as well as eight 1 week old fry from 2 females that released simultaneously.
Overall, I think P. demasoni is a great addition to any cichlid enthusiast's tank. They do not require as much space as some of the larger Pseudotropheus sp., yet still have the all of the same interesting behaviors and brilliant colors of their larger relatives. They may be a little expensive and hard to find, but they are well worth it.
© Copyright 1999 Marc Ludl, all rights reserved
Ludl, Marc. (April 01, 1999). "Pseudotropheus demasoni Konings, 1994". Cichlid Room Companion. Retrieved on January 22, 2019, from: https://www.cichlidae.com/article.php?id=257.