Angels - PageSuite

AMAZONAS
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Above, left to right: If
the opponent doesn’t
swim away, but spreads
his fins, then the dance
begins. Here a large
old male is challenging
a young tank-bred male
with orange-tipped
pectoral fins. The older
these fishes get, the
longer the first rays of
the first dorsal fin grow.
Adversaries typically
carry the dorsal and
ventral fins stiffly
extended. Initially
they remain at a short
distance; as hostilities
progress they come
closer together and
use laterally directed
movements to send
little waves of water
toward each other.
These two are near
the end of their battle.
They have come
very close together
and the younger fish
(foreground) is about
to give up. It is unclear
why, but all disputes
end in this way and the
loser is not harmed.
territories. Females swimming into these little territories are not courted by dancing, but
approached from the front with gentle head nodding. If the female doesn’t swim away, the
courting male turns next to her, quivering briefly. They swim beside each other in the direction
of a spawning substrate—in my tanks this is a mop or a clump of Java Moss. This spawning
procedure can be seen every day; the entire group is constantly ready to spawn if well fed.
I collect the eggs regularly and incubate them in a bowl in shallow water. The eggs are around
the same size as those of other small blue-eyes, such as Pseudomugil gertrudae—about 1.2 mm
in diameter.
Not at all difficult
Unfortunately, not all the eggs developed in my tap water, which had a temperature of 77–
80°F (25–27°C), a pH of 7.5, and an electrical conductivity of around 350 μS/cm. I assume
that the species actually inhabits the swamps in the drainage of the Kopi, and thus lives in
very soft black water with a low bacteria count. In the case of eggs transferred to 100 percent
reverse-osmosis water, the larvae hatch after 10 to 12 days without problems. If I hatch them
in bowls filled with tap water, I have to help at hatching time (Evers, 2011).
I feed the adults daily with Artemia nauplii, live or frozen Cyclops and water fleas, and very
occasionally with very high-protein granulate. The frequent feeding of such granulate and
Artemia nauplii isn’t healthy for the fish. Like other small species of blue-eyes, the females, in
particular, become misshapen and fat if their diet is too rich. Their bellies become distended
and they must be put on a strict diet or you will lose them. Feeding them entirely on pond