Congo Killies - PageSuite

Right: The Giant Raphael Catfish,
Megalodoras uranoscopus, is a suitable
tankmate for the Pac-Man Catfish, since it
reaches over 2 feet (60–70 cm) in length
as well.
that were imported to Taiwan, I
purchased them and raised them for
more than five years. By that time,
the male had reached 25 inches
(63 cm) and the somewhat smaller
female was 22 inches (55 cm) in
length.
Courtship display
One day, I started to observe an
interesting behavior in my Pac-Man
Catfish. When the smaller female
approached the male, she began to
tremble, displaying with her whole
body. It almost looked as if there
were waves traveling along her large,
soft, fleshy body. Each wave lasted between two and five
seconds. These short signals prompted the male to respond
in a similar manner. It was always the female who
initiated this behavior, which I interpreted as a courtship
display. The display lasted up to two days and afterwards I
usually found eggs.
According to my observations, spawning always happened
in the morning. Most pairings occurred between
7 and 8 A.M., and occasionally later, up until noon. I
have never seen any reproductive activity outside of that
time frame. On the evening before a spawn the fish were
unusually active, and the trembling became more frequent.
While they appeared to be aware of the presence
of their keeper, they were not disturbed by it. The female
excavated a spawning pit by shifting her body sideways
in the substrate; the male circled the pit and guarded the
vicinity. The female stayed in the pit to dig deeper and
select a spot for the eggs. An established pit was usually
selected again in later attempts. Often, the sand was
removed down to the bare glass bottom, where the eggs
were deposited.
OPPOSITE PAGE: I. CHANG; THIS PAGE: H.-G. EVERS
Sticky eggs
When the pit was ready, spawning followed the next
morning. The female laid golden-yellow, 2-mm eggs that
swelled quickly and were soon enclosed in 1-mm jelly
casings. The eggs were very sticky and adhered to each
other. The male carefully moved over the clutch and
fertilized the eggs. During the act, his pectorals trembled
in a wavy pattern. The whole spawning event took about
10–15 minutes, during which some 100 to 300 eggs were
laid. Viable eggs remained yellow; unfertilized eggs turned
white after two to four hours.
For the next two to three days, the female guarded
the clutch. Most of the time she lay directly on top of
the eggs, but she eyed the surroundings vigilantly. The
eggs’ jelly-like protective casings became thinner shortly
before the hatch, and finally I saw 0.2-inch (5–6-mm)
larvae hatch out. The fry—relatively small compared to
the adults—had black eyes, but the body and head were
transparent with a huge yellow yolk sac. In the first hours
after the hatch the fry were scattered around the female,
but two days later they all gathered tightly and wiggled
their tails. At 81°F (27°C) the larvae consumed the yolk
sac within 7–10 days. They grew steadily and developed
an increasingly darker pigmentation.
Breeding Diary (2010)
Aquarium: 48 x 24 x 24 inches (120 x 60 x 60 cm)
Filter: External biofilter with supplemental aeration via a
power head
Lighting: Dim fluorescent tube without a timer and
hence irregular light cycles
Water parameters: pH 7.0–7.3
Water temperature: 81–82°F (27–28°C)
Water changes: One-third weekly
Substrate: Dark river-gravel without sharp edges, with a
particle size of about 0.2 inch (4–6 mm), which was later
removed for better hygiene when rearing the fry.
Food: Small live fish and thawed large shrimps every two
to three days. (Use caution: don’t overfeed! To induce
spawning, increase the rations.)
Tankmates: Initially, another semi-adult Lophiosilurus
alexandri and three Megalodoras uranoscopus. After the
first signs of courtship, they were removed. At the time of
the first spawning, the male was 25 inches (63 cm) total
length at an age of five to six years, while the female was
22 inches (55 cm) at four or five years old.
AMAZONAS
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