Congo Killies - PageSuite

(23–25°C). If it comes from forest regions in the highlands,
then the correct temperature range is 64–68°F
(18–20°C).
If the fish came from near the coast, as is the case
with Aphyosemion australe (Cape Lopez) or Aphyosemion
striatum (Red-Lined Killifish), for example, this indicates
warmer and not necessarily soft water. By contrast, the
water in the mountain streams tends to be soft. Again,
there are differences between rainforest and savanna areas.
A further hurdle to be reckoned with is the sex ratio
among the offspring. This can prove extremely skewed,
with up to 100 percent males or females. There are a
number of factors that influence sex determination, but
so far this has actually been proved only for individual
species under very specific conditions.
The most popular theory
suggests that the sex ratio can be
influenced to some extent by the
maintenance temperature for the
fry during the first two weeks. This
actually works for some aquarists,
but often only with particular species
with particular parameters. Often
their results cannot be repeated
elsewhere.
Another method involves putting
two fry at a time in a container and
keeping them there by themselves for
at least two weeks. This frequently
produces a pair. Unfortunately, this
method isn’t reliable either, and
also appears to be influenced by
other factors. Often the sex ratio of
offspring reared with the parents is
more favorable than that in youngsters
incubated externally.
around and mention the species groups with which you
definitely shouldn’t start—primarily those that come
from cooler waters. It is easier to heat the water than to
keep it permanently cool. Even without any influence
from lighting and pumps, under living-room conditions
temperatures will reach levels at which the fish won’t
necessarily be inclined to spawn.
Recommended starter species include Aphyosemion
elberti, A. striatum, A. marginatum, and A. australe. Listing
possible additional species would be a waste of time,
since they are not easy to find in the trade. Reliable
sources include enthusiasts you find through your local
fish store or aquarium society and online killifish club
websites and forums.
Species and crosses
The more closely Aphyosemion species
are related to one another, the
greater the likelihood that they will
hybridize. Whether their offspring
remain fertile over several generations
is another matter. However, it
cannot be stressed enough that creating
hybrids makes no sense. The fish
are already brightly colored enough;
there is nothing to be optimized and
molded, and crossing two species
isn’t a breeding achievement to write
home about.
A not unimportant question for
the beginner is, of course, which
Aphyosemion he should start with
and where he can get them. We will
turn the first part of the question
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