Author Archives: Paul_

“Here's lookin' at you, kid,” – but be careful. Otherwise it could happen that it will be the very last what a tank mate will be looking at. Under these beautiful green eyes are not less impressive teeth that makes the wolf fish Hoplias malabaricus a feared hunter. The owners of these from Costa Rica to Argentina spread species should, when being busy in the aquarium, always have a view of their “favorite”, since it can come to bite injuries. Due to its large habitat some only difficult to distinguish subspecies of H. malabaricus exist. For those the statements of size differ, but it is to be assumed that H. malabaricus can reach a size of at least 50 cm and a weight of 1,5 kg. It is thereby no fish for everyone and completely nothing for a community aquarium. For experienced owners of large tanks which search for the unusual they may be a challenge which could be looked at.(Photo F. Schäfer, Text K. Diehl)

It was illustrated on the homepage of Canadian fish exporter “Below Water” and designated as “Kitty” Tetra (“a new Hemigrammus-species, caught in Mato Grosso in November 2000). It is presented as Hyphessobrycon loweae in the February/March-issue of “Aquaristik Fachmagazin & Aquarium heute”. According to Dr. Géry there are “good correspondences” with Hyphessobrycon loweae (Costa & Géry). Similar to Hyphesobrycon elachys , the clearly lengthened belly fins of the males, a widely extended back fin as well as a widened, bent anal fin are particularly remarkable. Tail-, back-, belly- and anal fin(s) are transparent-yellowish to darkyellow-orange-red and lined in a deep shade of red. The animals measure a total length of approx. 39mm of female sex and 42mm of male sex (standard length 32 resp. 35mm). According to first experiences water around 10° dGH, ph 7 and temperature around 24°C is sufficient for the keeping. (Photo F. Schäfer, Text K. Diehl)

Once again we could discover a new and very beautiful tetra at AQUARIUM GLASER several months ago. It should be another undefined tetra species (from Peru), probably a type of Hyphessobrycon. The fish were almost full-grown and the sexes rather sure to distinguish. We bought three pairs, which got used to our aquarium conditions without diffulties (approx. 10° dGH, pH 6.5-7, temp. 25°C). Within the following weeks of good feeding they were growing another few millimetres to a final size of 52-46mm (m-f). We could observe courting of both sexes almost every day. The shiny purple-blue body colouring with the yellowish head part and the red fins show to advantage in a not too much lighted aquarium. The colouring of the (belly-, anus- and tail-) fins of the females is more transparent-pink, while the colouring of the males fins can reach a bright intensive red. There are hardly any differences between the body colouring and form. The males show a (loose) territory behaviour, but there are no serious aggressions to other fish. Also the laying of the eggs was not long in coming in a separate 10l-breeding tank. The breeding caused a lot of problems, e.g. in the beginning the rate of coming out fish, then the first intake of food, finally an enormous proneness for water changes and -pollutions and extreme slow growth and development of (fin-) deformations if the breeding conditions are not optimal. Despite the partly frustrating experiences mentioned above, we continue trying to improve the “breeding rate” in order to keep this tetra at least in our aquariums.(Photos & Text von P. & M. Hoffmann)

This small characin is a very attractive fish and a fast swimmer as well. It could be determined as a representative of the Hasemania genus, because it misses the characteristic adipose fin, which is one of the features that determine characins. Up to now we used to have only one species belonging to this genus, which is the well known silvertip tetra, Hasemania nana. An exact determination of the new tetra has failed. Even Dr. Géry (France) could not determine this fish from just photos. This could mean that we have a new and undescribed species here. The only information about its origin is that it comes from Brazil, but no exact location has been given. There is a clear sexual dichromatism between the genders because the male have a mood depending colour ranging from orange to dark red of large parts of the body and the fins. The female however has a yellowish colouration. The breeding is not very difficult, however the eggs and fry, as with the silvertip tetra, are very small and the young fish grow relative slowly. (Text: P. u. M. Hoffmann, Foto: P. Hoffmann)

This fish is an extreme attractive tetra of the species Hyphessobrycon. There is no exact scientific definition of this kind yet, which grows up to 50mm minimum. Its body colouring looks a bit like a crossbreeding of three-banded-tetra (Hyphessobrycon heterorhabdus) and the black neon tetra (Hyphesobrycon herbertaxelrodi). This tetra has also got the red upper half of the iris as well as the other two species mentioned. A broad black stripe starts behind the gill lid, where it leads down vertically wedge-shaped, depending on the mood, and continues to the end of the tail fin. A golden line leads parallel above this stripe and ends in the region of the tail root. The gill lids are also shining yellow-gold depending on the illumination. The most striking distinguishing marks are his different intensive red coloured fins. Especially the tail- and fatfin as well as the lower rim of the anal fin of both sexes can take on a bright red, which is more intensive at the males. The males are distinguished from the females by the fuller belly of the latter when they become fertile. Other than usual at similar Tetras, the males seem to become a bit bigger than the females. At the moment this is not absolute definite yet though. The animals probably come from the catchment area of Rio Madre de Dios in Peru, whereas the exact habitat is unknown. Among “Peru-emperor-tetra” this tetra is also getting called “Puerto Maldonado Red Fin” (Puerto Maldonado: City on Madre de Dios). The first wild caught animals turned out to be quite unproblematic and absolute peaceful in keeping. Breeding small quantities was also successful meanwhile.(Photo F. Schäfer, Text K. Diehl)

The blind cave fish Astyanax jordani is a fish adapted to the life in absolute darkness. Characteristic for animals living in the dark is the missing of eyes, as well as missing pigmentation of the skin. It is assumed that Astyanax jordani developed from the seeing species Astyanax mexicanus. This could have happened by a wash in (e.g. with a flood) of A. mexicanus in caves and their continuance there over numerous generations. The maintenance of blind A. jordani is completely the same as for their seeing relatives. They compensate their blindness over the lateral line system, as well as over smell and taste senses. So they are well oriented in their aquarium and very successful in their search for food. As soon as the food arrives in the aquarium A. mexicanus gets very alive and will cheat out some seeing fish at the search for food. Thus they can be maintained without any problem in the community tank. (Photo F. Schäfer, Text K. Diehl)

In the last years some quite difficult to classify new species of characins arrived from Paraguay. Usually they belong to the genera Creagrutus, Hemibrycon and Piabarchus. As a common characteristic a high swimming activity can be called for all species of this relationship. They need thus tanks, with a large free swimming area. Thus long stretched aquaria are ideal for them. There a strong current can be produced with the help of a centrifugal pump, in which they can organize their “swimming contests”. They like to jump, a complete cover helps to avoid losses. According to their origin they do not like it durably hot, an unheated aquarium is very pleasant and preserve the purse of the owner. They do not place increased requirements on their nutrition, living and frosted food are preferred, but they can also be fed with flake food.(Photo F. Schäfer, Text K. Diehl)

This new African tetra, presented by Dieter Bork in “Das Aquarium” 12/01 as “pastel-congo-tetra”, comes from Lake Maindombe (also known as “Lac Leopold II”) in the Democratic Republic Congo (Zaire). Ornamental fish breeder Winter was able to multiply them in a bigger number of pieces. The fins of the males are pulled out beautifully and nicely coloured (the “fringed” pulled out and dark lined back fin of full-grown animals reaches to their tail fin). The colouring of the females is plainly less spectacular (silver-grey body and “short” transparent fins). During the often noticeable courting the males develop bright yellow-orange fins, the body colouring is also getting more intensive and the usually hardly visible oval shoulderspot is becoming plainly wider and deep black. The spawn grains are conspicuosly big (approx. 1.2-1.4mm), crystal-clear and not adhesive. The growth of the babies is very slow. Altogether it is a very attractive, lively, peaceful, easy to handle, new tetra, which neither bothers other fish nor plants and whose whole beauty is showed to advantage under slightly muffled light.(Photo von F.Schäfer, Text von P. & M. Hoffmann)

Because of their rhomboid body form these animals remind one a little of African tetras of the species Phenacogrammus or Bathyaethiops. Except from Rio Oyapock Astyanax leopoldi are also said to be found in Rio Approuague. They were named in honour of King Leopold III of Belgium, who attended an ichthyological expedition to Rio Oyapock in 1962. Fortunately we soon succeeded in breeding, even though this tetra was not always unproblematic. Especially when doing too generous water changes with raising the pH-value fish of all ages occasionally respond with symptoms of a “shock” (body gets white), from which they somtimes do not recover. Apart from that these are very enduring, peaceful and “grateful” fish. Although they are not really coloured newcomers, they surely earn a permanent position in the aquarium hobbyists.(Photo & Text von P. & M. Hoffmann)

According to Weitzman this tetra, which was described only recently (Zarske & Géry 2001) belongs to the relationship of the “Rosy-Tetra-Group” (in the widest sense). In 1995 the first animals came to Germany, caught in a tributary of Rio Acanti, Columbia. All specimen, which are currently on the market are said to be descended from the first few imports. Already shortly after its discovery really masses of this fish were bred and offered on the market (mostly under the name Astyanax spec. or Hyphessobrycon ecuadoriensis until its scientific description), which is why the at first considerable price quickly fell to a “lower tetra level”. Hyphessobrycon columbianus is an enrichment for the hobbyists because it is colourful, peaceful and easy to breed, although it fades when not kept under optimal conditions. The water should rather be a little cooler (under 25 °C) and harder, the pH-value should be neutral to slightly alkaline. The animals also seem to be sometimes susceptible to (bacterial?) infections. (Photo & Text von P. & M. Hoffmann)

Until a few years ago Red Phantom tetra, Hyphessobrycon sweglesi was easy to identify, even though under the name of Megalamphodus sweglesi. Lately “Red Phantom Tetras” appear more often, which are very similar to it, but also show other characteristics. It stays (temporarily) unclear, if they are own species, subspecies or “local forms”. Interested hobbyists, who would like to breed this tetra should know that the young fish are very small and prone to “infusorios” and that they require smallest life food in the beginning , if possible. Their growth is extreme slow during the first weeks/months. For this reason wildcaught ones are prevailingly put on the market.(Photos & Text von P. & M. Hoffmann)

This tetra was introduced to us under the name of “Inpaichthys sp. Lapislazuli” in February 2002 by Mrs. Glaser-Dreyer (Aquarium Glaser GmbH). On the (Japanese) internet it is called Lapis tetra. It was imported in a bigger number of pieces without exact declaration of place of discovery. The males are growing up to at least 4cm and are far more colourful and stronger with a lengthened back- and anus fin than the lighter females, which are only approx. 3.5cm long. They are almost always moving, very voracious, peaceful and the males are constantly busy with fights for their territory among themselves. The breeding was a success for the authors.(Photo F. Schäfer, Text K. Diehl)