Breeding Fact Sheet No. 5

Bleeding Heart Tetras - old and new

For almost 50 years, the "Bleeding Heart Tetra" has been a staple in community tanks around the world. Introduced from Columbia and Peru in 1956 as the "Tetra Perez" it has been part of a number of minor mysteries. The first of these I suppose is the real name of the fish. For some years after its introduction it was called Hyphessobrycon rubrostigma (Hoedeman 1956) but the valid name was soon determined to be Hyphessobrycon erythrostigma (Fowler 1943). Both names translate to 'red spot' and refer to the red marking over the 'heart' that is present in all Bleeding Hearts.

There were a couple of other errors made in describing this fish when it first arrived. Sterba, a well known and respected ichthyologist and author of the time, apparently didn't have the patience to wait and described them as growing to only about 1.5". In reality, Bleeding Hearts are one of the larger tetras and grow to at least 3". Axelrod, in his looseleaf edition of Exotic Tropical Fishes managed to get the size about right but states they "will spawn readily". Most sources, fifty years later, still describe the species as ‘not yet spawned in aquaria’ - not exactly a 'ready spawner' it seems!

The biggest source of confusion, at least for hobbyists, however, has been the fact that there is not one Bleeding Heart, but three. At least there are three that are imported and sold under that name.

The latest of these to appear is Hyphessobrycon pyrrhonotus (Burgess 1993), known usually as the Flameback Bleeding Heart. The dorsal area of this species can be bright red - hence the name. These fish occur in the Rio Negro basin of Brazil and in the past have only rarely been available. Recently, in the past three or four months, they have been for sale in at least one nearby store and I have seen them listed on some importers price lists. If the bright red colour on the back of this fish maintains itself in aquaria, it will probably be more popular than the traditional Bleeding Heart. To date I have not heard of any captive spawnings.

The third species, sometimes called the Lesser Bleeding Heart is Hyphessobrycon socolofi (Weitzman 1977). Named after the renowned Ross Socolof, this fish is found in the Rio Negro basin of Brazil and has been in the hobby since about 1980.

Especially when smaller, they are easily mistaken for the 'normal' Bleeding Heart, Hy. erythrostigma. I bought my first group of these fish about twenty years ago as "Bleeding Hearts" and it was several months before I truly realized that there was something different about them. At that time there was little information available in the popular literature but I finally did manage to identify them and they have been one of my favourite tetras ever since. In my opinion, a school of adult socolofi are much prettier than erythrostigma.

Over the years I have kept my eyes open for these fish. I have seen them on quite a few occasions but always sold only as "Bleeding Hearts". In some cases the tanks have contained both species - likely the result of two different shipments being placed in the "Bleeding Heart tank". On more than one occasion I've asked a pet shop employee to pick specific fish for me from one of these mixes and never has he understood why - even when I've explained that they had two different species in the tank.

At the size "Bleeding Hearts" are usually sold, the two species are difficult to differentiate. Probably the best way (although not a guarantee), to separate them is by the anal fin pattern. In the normal Bleeding Heart, the white colour in the anal fin, (particularly the male), continues to the bottom of the extended front rays. In socolofi, this colour only runs along the top of the fin. The dorsal fin of adult male erythrostigma is also longer. But it's easy to make mistakes especially with the normal mid-size pet shop specimens!

Once you have a group of fully-grown socolofi, determining the sexes is relatively easy. Healthy, well-fed females are noticeably fuller in the girth than are males. As well as this, the tip of the male's dorsal fin is white and that of the female, red. The same colour difference is found in the anterior portion of the anal fin.

From the first time I accidentally discovered these fish about twenty years ago until now, I suppose I've had them three or four times. Each time, for one reason or another, I've neglected to try to breed them. This time I decided I'd better get moving.

A ten-gallon tank was set up with a spawning grid that covered almost the entire bottom. The grid is a piece of plastic eggcrate cut to size with screening glued to the top. This is the plastic screen used for needlework and crafts. A couple of sinking spawning mops were placed on top of the grid. The water was adjusted to about 200 Fs with RO water and a pair of socolofi was added. Temperature was set to 80°F. Lighting was just the normal fish room fluorescent lights on the ceiling.

The fish were left to their own devices for several days and proceeded to do nothing. At that point half or more of the water was removed and replaced with slightly cooler RO water. This resulted in a conductivity of about 100 Fs and the next day the fish spawned.

The adults were removed and the tank covered to keep the light down. The eggs hatched in two or three days and were free swimming with no egg sac in another three days or so – quite typical for most Hyphessobrycon species.

The fry were fed a dry powder food and vinegar eels as first foods. I estimated there were approximately 200 of them and at the time of writing this seems to have been a reasonably close guess. Water changes of about half a litre a day were made using local tap water (300 Fs) so that the fry slowly became accustomed to the water they would live in as adults.

The fry grew very slowly. After about ten days I added microworms to the diet. They seemed to eat these well, especially the variety know here as "Walter Worms" (don’t ask me why), which are even smaller than the traditional type. After another week they were large enough to eat newly hatched shrimp and have grown steadily ever since. I even had a few Aphyosemion congicum hatch at about that time and I put them with the tetras. So far they seem to be doing fine and, as would be expected, have outgrown the socolofi.

As the fry grew and the first of them began to "round out" and take the shape of the adults, the first marking to appear was the black spot in the dorsal. At about ten or eleven weeks of age, the largest of the fry are about three quarters of an inch long (TL) and the smallest about one quarter. They'll soon have to be sorted out to keep them growing.

I've wanted to spawn this fish for quite a while and the procedure turned out to be surpisingly simple. I surmise that the key is using young, adult fish and water of very low conductivity. The next attempt, I suppose, is to give Hyphessobrycon erythrostigma a try.

by Paul McFarlane (Hamilton and District Aquarium Society, Hamilton, Ontario, Canada)