Bleeding Hearts - Old and New
by Paul McFarlane
From the Monthly Bulletin of the Hamilton and District Aquarium Society
Aquarticles
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 loose-leaf 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 s with
RO water and a pair of socolofi was added. Temperature was set to 80F. 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 s 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.
Pretty typical for most Hyphessobrycon species.
The fry were fed APR mixture 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 s) 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, 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
surprisingly 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.
|