|The dominant male of the Pseudotropheus demasoni breeding colony. Photo by Frederic Potvin.|
You are looking at a 180 liters tank (48 gallons long) tank, (122x30x57 cm, 48"X12"X15") furnished with moderately fine natural gravel, and piles of rocks arranged to form as much hiding places as possible. The filtration is performed by a canister filter (FluvalTM 303, Hagen), and the exhaust spray bar provided water movement at the surface for oxygenation of the tank. The temperature set at 26°C (79°F) is maintained by a 200W Thermal Standard (Hagen) heater. This is an old tank, metal framed, which has been included in a hand-made wooden cabinet since several years ago, and the cabinet was painted black. I personally modified the lightning system, including 2 122 cm (48") fluorescent into the cabinet. The fluorescent tubes consist of a "Day glow" (full-spectrum) and a cool white standard bulb. Floating plants are present as Lemna minor, water lettuce and water hyacinths thrive on the surface of this tank.
|A brooding female Pseudotropheus demasoni. Photo by Frederic Potvin.|
|Dither fish, Boelkha fredcochui. Photo by Frederic Potvin.|
|Incubation jar where I put the newly stripped fry. Note the two week old fry under the sponge. Photo by Frederic Potvin.|
This old and nice tank became recently the new home of my breeding group of Pseudotropheus demasoni. I bought a group of 12 individuals before and during the auction last summer at the ACA convention in Chicago. Those were initially placed in a 15 gallons tank (all my other bigger tanks were full after the auction!!!) with gravel as sole decoration. Three months later, I saw the first ovigorous female, and the aggression had risen in those small quarters so the fishes were moved to a 95 liters (25 gallons) tank furnished with gravel and piles of rocks. It then took me a few more spawnings and some more thorn fins to decide me to prepare the 180 liters (48 gallons) for them as described above. I believe now my breeding group is well settled in this tank, and I harvested already several ovigorous females. The water conditions are steady with a pH of 7.8 and a hardness at 12 German degrees. The nitrogen cycle is managed by weekly water change of 50% of the total tank volume.
The fishes are fed twice on a daily basis with a variety of foods including good quality flakes, two different brands of cichlid pellets, roman lettuce, and some frozen food of my composition (beef heart, fish meat, whole shrimps, spinach, roman lettuce and some gelatin). The roman lettuce is important and there is always a fresh leaf in the tank so the fishes can graze on it. Under this regimen, I find that the females spawn regularly. The only disadvantage of this set up is that those fishes are rather shy, so I found beneficial to place some dither fishes in their tank. For this purpose, I used some blue tetra (Boelkha fredcochui) which wander around in a reassuring way for my group of Pseudotropheus demasoni.
Every two weeks, I remove all the rocks in the tank and capture the ovigorous females. I strip them and put them back in the tank, reorganizing the whole decor afterwards. This gives a chance to the females to avoid being consider as outsiders upon their return in the tank. The fry/eggs are placed in a 1 gallon glass jar with an active sponge filter (Hygro-SpongeTM). The eggs are placed in a home made egg tumbler easily made as follows. I take a carbon cartridge sold to use as complement chemical filtration on the exhaust tube of UGF's. I empty the cartridge of the carbon and glass wool inside, I put the eggs inside and shut the lid (operation done entirely in the tank water) and stuck this egg container in the exhaust tube of the sponge filter. I then adjust the air flow of the filter to gently tumble the eggs. I keep the fry is this jar until they are free-swimming, at which point they are transferred in a small tank on their own, bare bottom and filtered with a corner filter. The water conditions are the same in the rearing tanks. At this point, I feed the fry newly hatched brine shrimps, micro-worms and vinegar eels (Anguilla sp.). I add some powder fry food and spirulina powder once in a while. The fry grow steadily but rather slowly under this regimen.
The Pseudotropheus demasoni is a nice new addition to the fishroom of any Malawi cichlid enthusiast. I was told they were rather hard to keep, but mine thrive under those conditions.
© Copyright 1998 Frederic Potvin, all rights reserved
Potvin, Frederic. (七月 25, 1998). "Pseudotropheus demasoni Konings, 1994". Cichlid Room Companion. 檢索 四月 25, 2017, 來自: http://www.cichlidae.com/article.php?id=256&lang=zh.