Terms and Conditions
Please read the following before you place an order.
Glass knifefish
£8.00
Eigenmannia virescens
| Scientific Name | Eigenmannia lineata, Sternachus virescens, Sternopygus lineatus, S. tumifrons |
|---|---|
| pH | 6.2 – 7.2 |
| Max Size | 45cm (17.7") |
| Temperature | 23-28°C |
The Glass Knifefish is widely distributed across South America, from the Rio Magdalena drainage east of the Andes in Colombia, to the La Plata River basin in eastern Argentina. It can be found in a variety of different biotopes due to the large area of distribution, but in general, it prefers deep ponds with aquatic substrates rich in plant debris, and is also found underneath islands of floating meadows in the floodplains. This nocturnal oddball is a micro-predator of insect larvae and small fish, and possesses a weakly discharging neurogenic electric organ and ampullary electro receptors that are distributed from head to tail. This means that the fish can not only sense electrical impulses, but can send them as well. These electrosensory systems are used mainly for electro-location, navigation, and communication, and are relatively weak as electric fish go, so pose no risk to the aquarist. This is a endearing fish which has an elongate, semi-transparent body. It moves in a graceful manner by undulating the long anal fin - which stretches the length of the belly, from just under the base of the pectoral fins to the caudal peduncle - and is capable of swimming forwards or backwards with ease. The Glass Knifefish is reasonably easy to keep, provided that some key requirements are met. Firstly, the male fish in particular grow very large, and, like other knifefish, cannot really bend - so a voluminous aquarium (at least 6ft long and a minimum 2.5ft wide) is a must. Secondly, the knifefish must be provided with a choice of shady hiding spots e.g. wide PVC tubes, rocky caves/overhangs (do ensure such structures are stable), large tangles of driftwood, and leaf litter (dried Indian Almond leaves are ideal, but will require periodical replacement). The lighting should not be too bright as these nocturnal fish are sensitive to intense illumination; if the tank must be brightly lit in some areas, provide plenty of broad leaved aquatic plants and floating species to help diffuse the light. Nonetheless, there absolutely must be areas of darkness within the tank that the fish can retreat to during the day as necessary. The substrate should consist of soft sand in order that the fish may grub about safely when searching for food, and so that the delicate anal fin does not become torn in any sharp gravel. Filtration should be efficient, but water movement not too vigorous. A consistent maintenance regime encompassing regular small partial water changes is important, as these fish are sensitive to elevated nitrate and sudden changes in water chemistry. Glass Knifefish are of a peaceful nature and are somewhat timid. They can be safely kept alongside other fish of similar size and temperament, and their gregarious nature means they should be kept in good sized groups of 6 or more.
Eigenmannia virescens
| Scientific Name | Eigenmannia lineata, Sternachus virescens, Sternopygus lineatus, S. tumifrons |
|---|---|
| pH | 6.2 – 7.2 |
| Max Size | 45cm (17.7") |
| Temperature | 23-28°C |
The Glass Knifefish is widely distributed across South America, from the Rio Magdalena drainage east of the Andes in Colombia, to the La Plata River basin in eastern Argentina. It can be found in a variety of different biotopes due to the large area of distribution, but in general, it prefers deep ponds with aquatic substrates rich in plant debris, and is also found underneath islands of floating meadows in the floodplains. This nocturnal oddball is a micro-predator of insect larvae and small fish, and possesses a weakly discharging neurogenic electric organ and ampullary electro receptors that are distributed from head to tail. This means that the fish can not only sense electrical impulses, but can send them as well. These electrosensory systems are used mainly for electro-location, navigation, and communication, and are relatively weak as electric fish go, so pose no risk to the aquarist. This is a endearing fish which has an elongate, semi-transparent body. It moves in a graceful manner by undulating the long anal fin - which stretches the length of the belly, from just under the base of the pectoral fins to the caudal peduncle - and is capable of swimming forwards or backwards with ease. The Glass Knifefish is reasonably easy to keep, provided that some key requirements are met. Firstly, the male fish in particular grow very large, and, like other knifefish, cannot really bend - so a voluminous aquarium (at least 6ft long and a minimum 2.5ft wide) is a must. Secondly, the knifefish must be provided with a choice of shady hiding spots e.g. wide PVC tubes, rocky caves/overhangs (do ensure such structures are stable), large tangles of driftwood, and leaf litter (dried Indian Almond leaves are ideal, but will require periodical replacement). The lighting should not be too bright as these nocturnal fish are sensitive to intense illumination; if the tank must be brightly lit in some areas, provide plenty of broad leaved aquatic plants and floating species to help diffuse the light. Nonetheless, there absolutely must be areas of darkness within the tank that the fish can retreat to during the day as necessary. The substrate should consist of soft sand in order that the fish may grub about safely when searching for food, and so that the delicate anal fin does not become torn in any sharp gravel. Filtration should be efficient, but water movement not too vigorous. A consistent maintenance regime encompassing regular small partial water changes is important, as these fish are sensitive to elevated nitrate and sudden changes in water chemistry. Glass Knifefish are of a peaceful nature and are somewhat timid. They can be safely kept alongside other fish of similar size and temperament, and their gregarious nature means they should be kept in good sized groups of 6 or more.
Shipping Policy
We ship our fish with DX, the only courier in the United Kingdom who are licensed to ship fish and other livestock by the Department for Environment, Food & Rural Affairs.
We can guarantee next-day delivery for £32 between Monday and Thursday for orders placed before 1pm and for boxes up to 25kg.
We are able to ship on Friday for a Saturday arrival, but this service will cost £45.
Please note that we will not send a fish that day if overnight temperatures are due to be lower than 6 degrees Celsius.
Some of the fish we stock can be sexed and are sold in a pair of 1 male and 1 female. Please bear in mind, however, that we attempt to match them correctly to the best of our anatomic knowledge but there can be some mistakes, as it is not always guaranteed that the fish will be oppositely sexed.
All our fish are packed in double thickness bags for their safety and security.
The bags are then packed into a polystyrene box with a 40h heat pack and a cardboard outer.
After a shipping date is agreed upon, it is the responsibility of the buyer to be at home when the package arrives.
Once the fish arrive it is your responsibility to acclimatise and then quarantine them using the dripping method. All fish leave our care in good health.
International Shipping
On account of stringent regulations and certificates surrounding the shipping of live fish reintroduced following the United Kingdom’s (UK) exit from the European Union (EU) in 2016, Aquarium-Fish Ltd are no longer able to ship to the EU.
However, we are able to ship anywhere else in the world. Please get in touch if you reside outside the UK and are interested in making a purchase to discuss shipping costs and times.
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