female swims with an egg in her fins,
looking for a good place to put it, which
is usually in the clump of moss and only
rarely on the glass. Spawning is a bit wild,
and the females are chased vigorously
through the Java moss. The activity stops
around midnight, but even if we are not
present to witness the spawning it is
easy to notice the clumps of moss strewn
around the tank, and the large eggs can be
seen by close inspection.
C. weitzmani fry three weeks post-hatch.
C. weitzmani fry at six weeks post-hatch.
Raising the Fry
Corydoras weitzmani are not egg eaters,
but I prefer to collect the eggs and incubate
them in another small tank. They are
large, hard, and adhesive, and they can be
gently collected with the fingers. It is also
possible to clip the moss with scissors to
harvest the eggs.
They hatch in 120 hours at 24°C ( 75°F).
The larvae are unusually large, and three or
four days later, when they have absorbed their
yolk, it is necessary to start feeding them.
We can use microworms, but freshly
hatched Artemia nauplii are better. The
fry can also eat extremely fine prepared
foods, such as powdered flakes. With
heavy feeding of brine shrimp the fry will
soon have golden pot bellies. With such
heavy feeding three times per day, we
must vacuum out all detritus a half hour
after each feeding, and change one-third
of the water in the tank daily using water
of the same temperature and chemical
parameters. Cleanliness is imperative,
since the fry are very sensitive to harmful
microorganisms that would otherwise
flourish. These can quickly wipe out an
entire batch of fry, and once they take hold
it is very difficult to save any of the fish.
These infections appear seasonally. I had
problems with fry loss during the spring,
but not during the winter.
At the age of two months the fry are 2
cm (¾ inch) long and have attained adult
coloration. The best water parameters for
developing eggs are a pH of about 7, GH
about 3, and KH below 1. Adult fish have
no special requirements in terms of water
chemistry, and a temperature of 20° to
24°C ( 68° to 75°F) is fine.
At this time Corydoras weitzmani
is still a bit expensive, but thanks to
the ease with which these “holy grail”
fish breed, they should be available to
all cory enthusiasts in the very near
A two-month-old C. weitzmani juvenile.