By Tony Jochman
Demasoni 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 and more aggressive than other species in their family (this may be a matter of opinion).
I purchased my first group of 14 P. demasoni about 1 year ago at an Aquabid auction. They measured about 1 ¼” long, and were placed into a 30 gal. tank. I lost 11 due to the aggressive nature of this fish. The group now consists of the dominant male, who measures about 3”, 1 female, who measures 2”, and a subdominant male about 2 ½”. Other tank inhabitants are 4 Cyrtocara moorii 5”, a pair of Tropheops sp.”Red Cheek” 6”, plus three smaller females 3”, and a pair of Labeotropheus fuelleborni “OB Marmilade Cats”.
The group is kept in a 40 gallon long aquarium. Lighting consists of 1 48" 40 watt fluorescent powerglo tube. The substrate is a white and black sand mix 6 to 1. Decorations consist of some locally collected smooth stones and some flat stones bought from the local landscape shop. 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 fake plants in the tank, and some hanging plants on the back for the holding females to take refuge. The tank is filtered by 2 Penguin Bio-Wheel 330 outside power filters. These filters each have 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 to 78 degrees by heating the whole room. 50% of the water is changed every 3 days with tap water treated with a water conditioner. The water parameters are as follows: temperature 78.0 F, P.H.: 8.0 to 8.8, and Hardness: ~400+ 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 flake and pellets, 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 foods. 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.
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!). What typically happens come spawning time: the male does his little dance, or jittering, in front of the females and if any are ready she will follow the male into the breeding pit. The male will then scrape his anal fin on the rocks to show the female a good place to place her eggs. The female will follow, lay her eggs, and then pick them back up very quickly. She does this a number of times, and as she picks up her eggs the male rubs his egg spots on the rocks as well. The male does this to entice the female to try to pick up his egg spots also; when she tries he will release his sperm into her mouth to fertilize the eggs. This process takes but a few hours.
I will let the female hold the eggs in her mouth for about 8-12 days, at which time I will strip the eggs. I do this one of two ways. The first is to put her in a breeding contraption called Aqua-Nursery; the other is just a plain old breeding net. When the female is ready I open her mouth and out come tons of little baby fry. I just use a Q-tip, but there are many other methods out there.
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.