I need this Information?
fish are fairly adaptable or we would not be able to
to keep them. However there are certain species which
are not so adaptable, especially when breeding them
is concerned, also there is optimum water condition
and quality for each species and while, by virtue of
their adaptability, they may survive in other conditions,
one will never see them in their best condition and
displaying their full colourful beauty.
is wrong with my tapwater ?
Nothing at all for the purpose
for which it is intended. The various water authorities
have a duty to produce water of a potable quality,
this means that it is suitable for humans to use,
without any additional treatments for the purpose
of cooking and drinking. lt does not mean it is perfect
for fishkeeping indeed as it is 'pure'
and some of these chemicals remain in the water it
follows that freshly drawn tapwater can in fact be
harmful to your fish. A case in point involves a gas
named Chlorine. This gas is used in the purifying
process and a certain amount becomes dissolved in
the water. Fortunately it is a volatile gas and will
escape to the air if the water is drawn from the tap
some 24 hours before use and allowed to stand in a
container with the surface exposed to the air. An
excess of Chlorine is quite capable of killing delicate
tropical fish and is unpleasant to the human palate
as you have probably discovered from time to time
when drinking water freshly drawn. The hardness/softness
and acidity/alkalinity of water from various localities
differ considerably so the serious fishkeeper must
make the effort, quite considerable at times to change
the nature of the tap water to that suitable for his
or her fish.
What does hardness/softness
and acidity/alkalinity mean ?
These are terms
used to describe certain qualities of the water concerned.
A simple explanation is that hardness/softness relates
to the amount of salt which the water has acquired since
leaving the cloud, from which it originated, as rain.
Hard water contains a lot of these salts while soft
water contains little. Acidity/alkalinity of water refers
to the ability to neutralise alkali/acid. It should
not be confused with the acid/alkaline ph value shortly
to be mentioned.
do I know what sort of water I have got ?
it is easy to check the quality of water by very simple
tests. There are various 'test kits' on the market and
although at first site they appear expensive, when one
considers that only a few drops from them are required
to carry out a test it follows that each package can
complete several tests, thus making the cost per test
reasonable. The normal procedure is to take a small
measured quality of water and to add to this a specified
number of drops from one or more solutions in the test
kit and then compare the resultant colour of the water
to the colour chart.
How do I measure hardness/softness ?
This can be measured in various
ways but generally accepted method relating to fishkeeping
is to use the German method of degrees, the higher number
of degrees the harder the water. The question of hardness
is complicated by the fact that the three types of hardness
are generally considered total hardness, carbonate or
temporary hardness and non-carbonate or permanent hardness.
What is Total Hardness
Total hardness is self explanatory
and refers to the total amount of salts which are contained
in the sample of water. The salts which are of interest
to us are bicarbonates, carbonates, and sulphate's of
calcium and magnesium.
What is Carbonate or
Temporary hardness ?
This is is a little confusing
in that it refers to the bicarbonates and small amounts
of carbonates (carbonates are not very soluble in water).
This type of hardness may be removed by boiling water
which converts the bicarbonate into virtual insoluble
carbonate which is precipitated. This is the explanation
for 'fur' found in kettles in hard water areas. For
those with soft knowledge of chemical symbols what happens
is as follows, CA (HCCO 3 ) 2 = (When boiled) Ca CO
3 + CO 2+ H2O. Calcium bicarbonate*, Calcium carbonate,
Carbon dioxide, Water (*Bicarbonate is know scientifically
known as Hydrogen carbonate) in other words the Calcium
bicarbonate is broken down into calcium carbonate (mostly
deposited on the inside of kettles or other vessel used),
Carbon dioxide (a gas which escapes into the air) Water.
What is Non carbonate
or permanant hardness ?
This is found by subtracting the
carbonate hardness from the total hardness and is caused
by the amount of calcium and magnesium present in the
water, normally in the form of sulphate's, nitrates
and chlorides. This type of hardness can not be remove
by boiling as in the case of carbonate hardness. There
are two main methods of removing this type of hardness,
first by boiling away the water in a closed vessel the
steam being conducted to a condenser where it is cooled,
usually by a water jacket and thus condensed back in
to water which is soft having left the salts behind.
This method is expensive in operation but does produce
virtually pure water, in fact this water is so pure
that it would not support fish life as certain 'trace
elements' which they need have been removed. The second
method is by ion exchange,as used to produce distilled
water for car batteries. This method uses an ion exchange
resin, often sodium zeolite,which will exchange its
sodium for the calcium in the water. The terms used
in respect of hardness using the German system are :-
0 GH= General hardness (permanent) :- 0 KH= Carbonate
What are the the other
methods of reducing water hardness ?
Go to our article section for
more information on reducing water
What is pH. ?
The pH value indicates whether
a liquid reacts in an acidic, neutral or basic (alkaline)
manner. The pH scale ranges from 0 (very acidic) to
14 (very basic), with neutral at about 7. The pH value
shows the concentration of certain ions which are responsible
for an alkaline or acidic reaction. Most freshwater
fish and plants can only survive in the pH range of
6-8. Some specialist species require ranges of 5 or
9. Maintaining a pH level of around 7, in the neutral
area is recommended for the following reasons.
As a one point fluctuation in
the pH value corresponds to a tenfold alteration in
the ions responsible for the change, any change in the
pH value is stressful for all the organisms in the water,
whether fish, plants or micro-organisms. Sudden deviations
in pH levels may lead to increased susceptibility to
disease in fish, poor growth in plants and may even
JBL Biotope aquarium water. JBL. GmbH & Co.KG, D-67141
Neuhofen/Plaiz, Germany. 33p.
This article first appeared in
the Greenock & District Aquarist Society newsletter
"The Angelfish" October 1995. no 4. and is
also duplicated on the Help index on Water