Satanoperca daemon
Geophagus daemon, or as this fish is also called, Satanoperca daemon fish, live naturally in the western part of the Amazon basin and also in the upper Orinoco River. The fish can be found in places with sandy substrate covered with a thick layer of fallen leaves and tree branches. Despite its intimidating name, this fish is generally peaceful, not causing any discomfort even to smaller neighbours. Despite this, keep Geofagus daemon is recommended for experienced aquarists, due to high water quality requirements and a specific diet.
The Satanoperca daemon is grey in colour. The entire body and fins are covered with fine bluish mottling. The anal, pelvic and lower tail fins are reddish. Three dark spots on the sides are the hallmark of this fish. Sexual differences are not pronounced, but during the spawning period the female and male can be distinguished by the rounded abdomen. The maximum size of these fish is 20-25 cm.
It is advisable to keep Satanoperca daemon in a small group of 5 - 6 fish. An aquarium of 500 liters is required for this number of fish. The internal design of the aquarium no special requirements - it is sufficient to use sandy substrate and place a few snags at the bottom. The substrate should not contain small stones, because the fish eat by sifting sand through the gills and stones can get stuck in them or injure.
Geophagus demons are calm and do not disturb other fish, and may therefore be kept with almost any peace-loving fish, even the smaller ones.
Water quality is of prime importance, as these cichlids are extremely sensitive to chemical deterioration. Therefore do not introduce fish into an aquarium in which biological equilibrium has not yet been established. Filtering with a combination external and internal water filter as well as replacing at least ½ of the aquarium water with fresh water each week is the best way to achieve the desired water stability. Water parameters: temperature 24 - 28° C, hardness dH 1-6°, pH 4,0-6,0.
Low, diffused light. About 10 hours of daylight per day.
It's not worth planting living plants, they're not likely to grow in this light. If you really want to decorate the aquarium, you can place in the aquarium, a few bushes of artificial plants.
The Satanoperca daemon fish feeds by sifting the substrate through their gills. For this reason, the fish are often called "ground feeders". The stomach contents of wild specimens mainly consist of small aquatic and terrestrial invertebrates, their larvae as well as plant seeds and detritus. In aquariums, fish are fed with small live and frozen bloodworms, artemia and flake food containing spirulina. Feed the fish preferably in small portions 3-4 times a day.
Reproduction
Under aquarium conditions to achieve spawning Satanoperca daemon is very difficult. It seems not known what is the incentive to start spawning, with the main requirements are a spacious aquarium, a varied menu and a strict regime of maintenance of the aquarium.
As it is very difficult to determine the exact sex of the fish, it may be best to purchase a group of young fish and allow the pairs to form naturally, this also requires a certain amount of patience as it may take at least a year for the fish to become sexually mature.
During the spawning period, the male does not particularly bother to bob his head near the female, spreading a fan all his fins. When the female shows interest in him, they both begin to build a nest in the ground, which is quite an impressive sized hole (in nature, it reaches 2x1 m). As soon as the pair begins to build a nest, all other fish should be removed from the aquarium.
The female lays a batch of eggs, and the male immediately fertilizes them. The spawning process is repeated many times until the female has fully spawned. In total, the female hatches about 200 eggs during spawning. The female takes care of the clutch, while the male guards the area close to the nest.
After about 3 days (at a water temperature of 27° C), the larvae hatch out and in 48 hours begin to swim freely under the care of their parents.
The fry are fed with Artemia nauplii.
