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Hierarchy
in the African cichlid community
African cichlids, even within the limits
of a tank, form a hierarchy. After keeping Africans for a while you
will see this taking shape. This is true both interspecies and
intraspecies. Thus, a male is usually the hyperdominant fish of the
tank (which means that it is not challenged by any other fish in
that tank AND may crossbreed if given the chance). This fish will
usually fight with other males (no matter which species they belong
to), will chase every other fish that comes close to it and this is
not only done during spawning time. It is more or less a sign of
dominance and it calls for a continuous display of its strength. If
this hyperdominant fish becomes sick or weakened then another fish
will take its place. This is especially true amongst mbuna species
and very profound among the most aggressive species. It is strange
but once a fish loses its hyperdominant place it is very difficult
for it to regain it. Fishes belonging to milder species never take
part in this ruling game.
Another
hierarchy is present within each species. The dominant fish will
display its strength all the time, especially towards rival males of
the same species. This is extended to females, too although it takes
too much effort and close watching to observe it. In short, it seems
that every fish in your tank knows exactly its place in the
hierarchy and this will not change unless a fish gains a higher
place, always using force to do it. One way to observe it is when
you have a sick fish. You will see that this fish is harassed by
almost every other fish in your tank. This is not cruelty; it
happens in every society. Your fishes are just rearranging their
hierarchy and sooner or later the sick fish will reach the bottom of
it. Unless treated the fish will surely die either because of the
disease or because of the bullying of the other tankmates. The
hierarchy is better observed when there is no spawning activity in
the tank. When spawning the male will chase any other fish as if
temporarily "forgetting" the hierarchy. Immediately after
spawning the order is established.
More related articles
:
Keeping African Rift Lake cichlids
in “harmony”
New
additions -
reintroducing a fish to the
tank Whenever
a new fish is added it starts from the beginning, that is from the
bottom of the rank. During the first couple of weeks the fish will
be chased and usually will not fight back as if checking the
existing order of things and see where it could stand. When it gets
fully acclimatized it will start to challenge fishes at the bottom
of the rank and after climbing some places it will find itself among
the others. It is astonishing to see that when a male Maylandia
lombardoi challenged my dominant male Melanochromis auratus and won
the fight, none of the other M.auratus challenged it. In contrast,
when it lost the fight against the hyperdominant Melanochromis
chipokae, all other chipokae, including females, fought against it
at some time or another (in fact I am not sure who started the
fights). After a while it became apparent to the rest of the tank
that the place of the M. lombardoi was second to the male M.
chipokae only.
The
same thing happens when a fish is removed from the tank for any
reason and returned after a couple of weeks. It has to re-establish
its rank, at least among its own species. Therefore one needs to pay
some attention and take certain precautions before introducing the
fish back in the tank. This is better done when feeding, thus giving
the newcomer a chance to find a hiding place. Another option is to
add the newcomer and then turn the lights off. This will also give
the fish some time. If you see that a fish is always chased and
harassed it it better to remove it from the tank. Such a fish will
sooner or later die and may become a life threat for the rest of the
inhabitants.
Sodium
bicarbonate (baking soda; NaHCO3) - Carbonate Hardness (KH)
This is the best
kept secret concerning Africans. All you will ever need to have a
well buffered tank is sodium bicarbonate (commonly sold in the super
market as baking soda). One tablespoon full of it per 150 liters
will create a buffer with a pH approximately 8.1-8.5 depending on
the starting pH of your tap water and the surface water movement.
The stronger the water movement the higher the pH you will get. If
you reduce the movement, more carbon dioxide from the air will stay
dissolved therefore your pH will drop to 8.1-8.2. I have 6 internal
filters (900 lt/h each) and two water pumps (2.300 Lt/h each)
creating a very strong water movement so almost all carbon dioxide
is released in the air again and my pH ranges from 8.4 (an hour or
so after feeding time because of the extra dioxide from the filter
bacteria) to 8.5 Since this chemical produces a buffer with the
maximum capacity around 8.2 the pH will never drop under normal
circumstances (this means provided partial changes are not
neglected). This will bring your KH to 11-12.
Please
consult the
Carbonate
Hardness table. In this table you
will know what is the content in carbon dioxide for any given pH /
KH combination. This table is important because it will show you
which is the safe pH range for any given pH for your fish which will
also make your live plants thrive. Please note that as much as 40
ppm of carbon dioxide have shown to be tolerated by the fish
however, most authors do not accept values over 25 ppm. You will
also note the true benefits of baking soda. In very high KH values
you will see that addition of too much carbon dioxide doesn't alter
the pH of your water significantly. This is very important because
carbon dioxide is produced in your tank even if you do not inject
it. Another observation is that at pH levels common for African
cichlids (over 8.0) the actual content of carbon dioxide is very
low. Practically, there is no carbon dioxide at any pH over 9.0
More related articles
:
The Chemistry of the
African Rift Lakes ,
Lake
Malawi - Water Parameters ,
Make
your own Salt Mixtures
Calcium
carbonate (CaCO3) - General Harndness General
Hardness (GH) is a measurement of the
content of your tank water in Calcium carbonate. Calcium carbonate
is slightly soluble in water and is mainly found in the more soluble
calcium bicarbonate [Ca(HCO3)2] form. If you want to know how many
grams of calcium carbonate equivalents are in your tank for any
specific water volume you should consult the
General
Hardness Table. This table
expresses volumes both in Liters and US gallons for your convenience
More related articles
:
The Chemistry of the
African Rift Lakes ,
Lake
Malawi - Water Parameters ,
Notes on Continuous Plant
Fertilization.. and a bit more
,
Make
your own Salt Mixtures
Temperature
See also the
Temperature
Conversion Table
More related articles
:
Keeping Temperature under control
,
Unit Conversion Tables
,
Final Water Temperature
,
Simple software which makes
our life easier
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