American Characin Basics
By Eric Rogne
From Splash, newsletter of the Milwaukee Aquarium Society
Aquarticles.com
More and more I become fascinated with small schooling community fish. Many species
come with red, blue, black, orange, yellow, silver, and gold. They bring an accent to
really set off the look of any planted aquarium, with other small aquatic life. The
schooling characteristic gives an aquarium a soothing flow. Their personalities in a
species only aquarium are much like cichlids. A sense of dominance and aggression most
displayed to others of the same kind. There are different levels of compatibility; which I
will not talk about at this time; it will be saved for a revised version. Males present to
females and spar off with other males just like cichlids. This would be in a manner of a
side to side presentation of erect fins to show body size. Very intriguing to see these
pint-sized animals combat each other. At times you can see a dominant male stake out a
section of a breeder tank where he wants to spawn. On the other hand they do not defend
the territory after spawning, and the eggs end up being scattered among the fine-leafed
plants.
Recently a few species of these American Characins spawned in my aquarium. You can find
that these Tetras are easy to spawn, but can be rather difficult to raise the fry under
aquarium living. These are the four species that I was able to spawn and raise to the
required time for BAP.: Hyphessobrycon columbianus (Colombian Blue Tetra), Aphyocharax
anisitsi (Bloodfin Tetra), Hemigrammus rodwayi (Golden Tetra), and Moenkhausia
sanctaefilomenae (Red Eye Tetra/Yellow-Banded Moenkhausia). I will give more
information about these species individually later. They were spawned and raised under
similar conditions. Differences will be pointed out with the individual information.
The way that I plan to have these species spawn is to have one or two community
aquariums where I can easily pull out the species that I wish to try. This could be a 20
gallon up to a 55 gallon. Choose what you have available. The water conditions can be
around a pH of 7.5 to 7.8, TDS of around 80-140, and a temperature of around 76 to 78
degrees F. The breeders are fed standard tropical flake as the staple. The day before and
day of transfer to the breeder aquarium I feed Cyclops and zooplankton. These are
freeze-dried foods, and yes live would be better in the best case. I travel a lot, thus I
have to use what is convenient.
The breeder aquariums are ten gallon bare bottom. I use a simple sponge filter. The
water conditions are set up anywhere from a week to a day prior to transfer of the breeder
colony. The conditions are set with a pH of 6.0-7.3 (most 7.0), TDS of 20-45, and a
temperature of 82-84 degrees F. This can vary with the species. These modifications may
not work with light sensitive egg layers, such as the Paracheirodon innesi (Neon
Tetra). I have not had experience with this grouping, but will get into it down the road.
I usually buy a group of one species with any fish. I used to spawn little fish like this
in standard trios or pairs. I found for me it takes too long to get the spawn. These fish
naturally spawn over a couple of days. I choose to develop using a group, usually two
males and four females. For species where females are much larger than males I use two
females and four males. By doing this you will risk predation on the eggs being laid, but
the spawning usually occurs the same day of placement in the aquarium. The breeders are
placed into the tank with a quick acclimation period. I call this a shock shift style. It
is also risky. The fish will be stressed for a few minutes, but most species handle this
procedure well. Do not do this to very sensitive tetras. The breeders of choice are also
fed just before being pulled from the community aquarium. I have found that some species
will not eat while in a species only aquarium, but they will spawn.
Now about décor. I use live plants ( Naja grass, and Java moss). I found these to work
best for me. The live plants not only give good hiding spots for fry, but also will
contain some live food. The plants are weighted down with small rocks. Other plants are
left floating to give the breeders hiding and privacy. The sponge filter is first placed
at a high current flow to give enough dissolved oxygen for the breeders. Lights are placed
on a timer for 12 hours per day.
Once the breeders have spawned, seen by looking under the bare bottom aquarium, they
are removed to minimize predation on the eggs. Do this as soon as possible. I have had
situations that resulted in losing the eggs, because I waited until the next day. At this
time I may add a black water extract and/or methyl-blue. A small rock is placed under one
of the corners of the sponge filter. This will prevent any of the fry from getting
crushed. The sponge filter is also slowed down to a very slow rate of one bubble per
second. The fry hatch generally for most species within 36 hours. The eyes develop within
three days of spawning. The eggs are 1mm. in size, and the fry 2mm. when hatched. They
require small food, thus use something with a small micron size that is also digestible. I
use a prepared powder that I will go more into detail on a later article.
The fry will grow at a stratified rate. Some grow fast than others. It will get to a
point where if you do not separate the larger from the smaller, you will end up losing fry
due to predation of siblings. Get other tanks ready ahead of time. These little bodies are
predators by nature. They will do best with live food (infusoria, and later baby brine),
but will convert to a prepared food when offered. They constantly look for food. My fry
only get fed once per day, but they should be fed multiple times per day. Water changes
are done once per week. Initially they are given 10%, and eventually will handle 25-50%
water changes in the weeks down the road. With these species a smaller water change is
better. I tend to get them acclimated over time to the conditions of the breeder community
tank.
Hyphessobrycon columbianus comes from the Darien region of
Colombia. It is a newer fish to the atlases of our fish community, but a fish that has
been enjoyed in the hobby for at least six or more years. Known as the Colombian Blue
Tetra, it sports a vivid blue color base on the body with red fins. Males are slightly
larger than females and have a longer dorsal fin. This species is very passive and will
only get about 5cm. They were spawned with two males and four females.
Aphyocharax anisitsi comes from the Rio Parana in Argentina.
This fish comes equipped with a silver body and red fins; hence the name Bloodfin Tetra.
The males and females are about the same size. Females will have a larger belly when
mature. The males on the other hand will have white tips on the pelvic and anal fins.
Watch out they are highly predacious on the eggs. Spawned in same quantity as the species
prior. The fry will also cause a big problem with preying on each other. They are slightly
nippy in nature. Not too bad, but may be better placed in a faster moving community
aquarium when adults.
Hemigrammus rodwayi can be found in Guyana. They sport a gold
body, thus being called the Golden Tetra. Males will be slightly smaller with brighter
gold color and a white tip on the anal fin. Spawned the same. Do not prey too bad on
spawns. Found fry in the aquarium with the parents. I had to leave the breeders in the
breeder aquarium for week. Fry do at least pick on each other as they grow (bigger on the
smaller ones). Rather peaceful in nature when adults.
Moenkhausia sanctaefilomenae comes from western Brazil over
to Paraguay. Plus this species has a not so much good name to pronounce in Latin. This
fish is silver in color on the body with a white/yellow and black stripe on the caudal
peduncle. The eyes are red and can be called the Red Eye Tetra. The body in squat and
compact. The males are brighter and much smaller than that of the females. This species is
very aggressive with each other, and the females bully the males around. I found it better
to use four males and two females to get them to spawn. Keep the adult breeders in a
larger group in an aquarium that is faster moving with other nippy fish (such as mid-sized
barbs).
That is it for now. Until next time, give American Characins a try. Happy trails.
|