Reproduction ensures the survival of a species, and nature has planned several
strategies for it. In the case of small eggs produced in large quantities, these
are often transparent, in an attempt to hide them from their predators.
Sometimes reproduction takes place in a communal tank, catching
the aquarist unawares.
As for large eggs, if there are only a few their parents protect them most of
the time. In both cases, the aim is to reduce the number of losses as far as possible.
In an aquarium, the intervention of the fishkeeper considerably increases the chances
of success, and the survival and proliferation of a species is normally guaranteed.
Reproduction techniques for aquariums
These vary according to the different families of fishes, and they will be discussed
in greater detail in the "Catalogs of Fishes" (pages 75 and 126). However, it is
possible to advance some general precepts on the subject here.
Choosing the reproduction site
Reproduction can occur spontaneously in a mixed tank, or in a specialized or
"regional" aquarium. This often happens with novice aquarists, unaccustomed to spotting
the approach of egg-laying in a female. In such cases the future of the fryis a
matter of chance. Some of them will serve as prey for the other inhabitants of the
tank, and the survivors are sure to have problems in getting enough to eat. since
they have to compete with adults. This is why it is advisable to use a tank specially
intended for reproduction.
Choosing the reproducing fish
Although it is sometimes difficult, at the best of times, to distinguish between
males and females, it is easy enough to spot a female's swollen stomach and the
attentions bestowed on her by one or several males - signs of the approach of the
It is therefore time to transfer the fish in question into the rearing tank prepared
for this purpose.
The selection and feeding of the parents are important factors
in successful breeding. Here, a pair of Colisa lalia, the male is on the right.