Betta Trading

Black Phantom Tetra

The Black Phantom Tetra, Hyphessobrycon megalopterus or Megalamphodus megalopterus, is a beautiful and peaceful little fish.  It comes from several river basins in Bolivia and Brazil.  These rivers include the Río Beni and the Río Mamore in Bolivia, and the Río Mamore and the Río Guaporé in Brazil.  It has also been reported from the Brazilian part of the Río Paraguay.  As far as I know it is not found in the lower part of the Río Paraguay in Paraguay.

The Black Phantom Tetra grows to about one and a half inches long.  (About 3.8 cm.)  Its life span is about 5 years.

Water Conditions
The Black Phantom Tetra is a tropical fish.  The places it is found in the wild are all in the tropics, and it does not appear to be found in the sub-tropical part of the Río Paraguay.  It is unsuitable for a cold water aquarium although it will take temperatures down to about 22 degrees C (72 degrees F), and is comfortable up to about 28 degrees C (82 degrees F).  It will survive a little above this for a short time.  In its natural habitat, this fish comes from soft acid water, but will adjust to slightly alkaline conditions with a moderate degree of hardness.

It is suitable for a mixed tank with a temperature of 24 degrees C (75 degrees F) with neutral pH and moderate hardness.

The Black Phantom Tetra is an omnivore.   In the wild it has a preference for live food, and in an aquarium will relish such foods as wrigglers, blood worms and Daphnia.  Frozen blood worms are also eaten readily.  Although it likes these foods, it is easily fed and will eat any good quality fish food.

The Black Phantom Tetra will eat at all levels, but favours the lower half of the aquarium more than many tetras.   With a mixed community of fish, it is a good idea to use a variety of food, including some that sinks before all the food gets eaten by the surface feeders.  Do not over feed.

This fish comes from waterways with plenty of plants and a well planted aquarium is recommended for them.

Like most tetras, the Black Phantom Tetra likes to be in a school, but unlike most, it is also happy in a pair.  Males will have “Mock Battles” with each other which rarely result in serious injuries. Males and female may also push each other around.

They are basically peaceful fish and are suitable companions for other small peaceful little fish, including all the tetras, the more peaceful of the barbs as well as Swordtails, Platies, etc.

Male Black Phantom Tetras have longer fins than the females and when in breeding condition, females become plumper, but the biggest difference is in their colour. The males have almost no red, while the smaller fins of the female both on the top and underneath them are red. The adipose fin, on the top of the body behind the larger dorsal fin is much more noticeable in the females than the males, because in females it is red while in the males it is grey.

The two picture above this section show a female on the left and a male on the right.

When the fish are in breeding condition, the colours of both sexes become more distinct, with the male showing its black fins more obviously.

Condition the fish well before attempting the get them to spawn.  If possible, live foods should be included in the conditioning period.

The Black Phantom Tetra is an egg scattering species.  To stimulate breeding, lower the pH to about 5.5-6, and decrease the general hardness of the water the below 4 degrees.  The breeding tank should have plants, both rooted and floating, and low light.

A female Black Phantom tetra will produce about 300 eggs.  These fish will eat their own eggs and fry, so the parents are usually removed after spawning.

The babies will need infusoria (protozoa) at first.  Commercial fry foods of suitable sizes can be used, but at all stages the young fish benefit from live food of the right size.

Pest Fish
With any pet fish, make sure it cannot get into natural waterways it is not native to.
Sources and Picture Credits
I gratefully acknowledge the valuable information I have got from the following sources:,,, and