Acestrorhynchus isalineae
Acestrorhynchus isalineae occurs naturally in the Rio Madeira River basin and the upper Amazon River basin in Brazil, South America.
Acestrorhynchus isalineae has an elongated silvery-olive body. The muzzle is pointed. The fins are colorless. The dorsal fin is high, displaced closer to the caudal plumage. Tail fin is bilobate. At the root of the tail plumage are two small spots of black and scarlet. A dark line runs along the entire length of the body, from the tip of the mouth to the root of the caudal fin. Adult females are usually slightly larger and fuller than males. The maximum size of fish reaches 10.5 cm.
Acestrorhynchus isalineae are relatively peaceful fish. Keep them preferably in a species aquarium group consisting of 4-6 individuals. These fish are not aggressive in relation to their species, but to other fish are very ruthless. They are able to swallow very large prey. The fish are cannibals and should not be added to the existing group of smaller fish. Young fish exhibit a pronounced gregarious instinct, while adults prefer to stay on their own.
Acestrorhynchus isalineae are active fish, they swim very fast and require large living space in the aquarium. The minimum size of the aquarium should be 120x45 cm. The aquarium should simulate the current, for example, using a water pump. As a substrate used a mixture of sand and small gravel. At the bottom have large stones and snags. You can plant plants that grow in sandy soil, as well as those that attach to scenery, such as Microsorum pteropus 'Trident'. The lighting should be adapted to the plants used. The aquarium lid must fit tightly, as these fish are good jumpers.
Water parameters: temperature 24-28° C, hardness dH 2-10°, acidity pH 6.0-7.5. Effective filtration is necessary, because due to the large amount of waste products from fish, it is difficult to maintain good water quality. It is necessary to install one or more canister filters and an additional sponge filter. Weekly water changes of up to 50% should be mandatory, as this species is sensitive to organic pollutants and fluctuations in water quality.
In the wild, Acestrorhynchus isalineae feed on fish. Newly acquired fish refuse to eat anything but live fish. Over time, they can be trained to eat frozen or dry food. Like the vast majority of predatory fish, this species should not be fed mammalian or bird meat, such as beef or chicken heart. Some of the lipids they contain are not absorbed properly by the fish, which can lead to excessive obesity and even organ degeneration. The food is given 1-2 times a day.
Reproduction
Acestrorhynchus isalineae do not breed under aquarium conditions.
In nature, females spawn in the water column, with the female remaining motionless and the male swimming around her describing the "figure of eight". The parents do not provide care for the eggs and future fry.