Tag Archives: Monodactylus

Monodactylus argenteus

16. April 2021

Moonies are magnificent brackish water fish. In pure fresh water they should be kept only temporarily, if possible, because they are very sensitive there. If it has to be freshwater, then the pH value must not drop below 7 and the nitrate value must not rise above 50 mg/l, nitrite is harmful even in very small amounts. In brackish or seawater (from 10-15 g salt/liter), however, they are robust animals. The fish we can offer right now are from Indonesia and were caught near Java.

Monodactylus argenteus should be kept in aquariums as large as possible, because they grow to a length of 15-20 cm and are very eager to swim. Juvenile specimens can be very incompatible with conspecifics, but this varies from individual to individual and there are also very compatible animals. It is best to keep them in a group of 10-12 (or more) so that any aggression is dispersed. A strong current and a good oxygen supply are further prerequisites to enjoy the animals for many years. The sexes cannot be distinguished externally. The fish spawn at night. They are free spawners without brood care.

The temperature should be between 24 and 28°C. They eat all usual dry, frozen and live food, if it fits into their mouth. Since these fish have a high metabolism, feeding several times a day in small portions is recommended. 

For our customers: the fish have code 436202 on our stocklist. Please note that we only supply wholesale.

Text & photos: Frank Schäfer

Monodactylus sebae

17. February 2021

The African Mono is widely distributed along the tropical Atlantic coast of Africa. As a completely euryhaline fish, it can freely change between fresh, brackish and seawater; it prefers to stay in brackish water. In its native range M. sebae is a common fish and is caught there for food. In the past, aquaristic needs were met by wild-caught fish from Lagos Bay, Nigeria, but for decades this species has only been available as offspring from Southeast Asia. 

M. sebae was one of the first marine fishes to be successfully reared in the aquarium. First breeding reports date back to 1968, planned breeding succeeded since the 1970s. The animals are free spawners without brood care, the spawn swims around during development, external sex differences are not known.

With a maximum length of 25 cm (but mostly around 15 cm, the animals are spawning at about 10 cm at the age of about 1 year) Monodactylus sebae is not a small fish, furthermore they are fast swimmers and should be kept in a troop (from 8 specimens upwards). So they require a correspondingly large aquarium. A value of 3-4 g/l has proven to be the ideal salt content. Monos are carnivores, which can be well fed with all common frozen and live foods. Dry food is accepted, but should not be used as a sole food. Monos like it warm, the water temperature should be between 25 and 28°C.

For our customers: the animals have code 150002 on our stocklist. Please note that we supply exclusively to wholesalers.

Text & photos: Frank Schäfer

Monodactylus kottelati

13. July 2018

Monos are classics among the brackish water fishes. Much of the aquarium literature about them mentions that these fish can be adapted easily to freshwater. But – what should this be good for? Is it really that difficult to put some salt (10-20 g per litre) in water? If one keeps them in brackish water and at a water temperature of about 26-28°C these racehorses among the fishes will bring only joy for the keeper. Currently we import quite often Monodactylus kottelati from Thailand. This fish reaches a length up to 20 cm and should be kept in a large (!) school of conspecifics. Otherwise they can be very quarrelsome.

For our customers: the fish have code 436242 on our stocklist. Please note that we exclusively supply the wholesale trade.

Text & photos: Frank Schäfer