Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02382949 2002-02-21
A
1
PD-6235
Process for the improvement of the water quality of
maintenance waters
The invention concerns individual processes for the
improvement of the water quality or correction and adjustment
of important chemical water parameters of biological
maintenance systems with use of ecologically neutral,
chemically- and microbiologically-acting water additives, a
combination of several processes for the improvement of the
water quality in biological maintenance systems, as well as a
single or multiple component product hereby usable.
In biological maintenance systems, e.g. aquaria, aquatic
terrains and garden ponds, due to the daily feeding of the
fish and other aquatic animals kept therein, it results in
cumulative changes of important chemical water parameters and
consequently in a continuous impairment of the water quality.
From this follows a correspondingly reduced quality of life
of the maintained fish and other aquatic animals.
If the starting water, e.g. tap water, possesses a sufficient
quality, then, by frequent partial or complete change of
water, an impairment of the water quality caused by the
maintenance can be countered. The procedure of the water
change is laborious and unpleasant for the aquarianists, for
the maintained fish and other aquatic organisms not without,
in part, considerable endangering due to undesired properties
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of the fresh starting water, such as for example chlorine or
heavy metals.
Consequently, a minimising of the water change frequency and
amount would be desirable.when - as described in the present
invention - it succeeds to suppress or to eliminate the
impairment of the water quality.
In detail,lit comes, in biological maintenance systems, to
the following changes of important water parameters impairing
the water quality. This is countered, in part, by already
known measures.
PO An example for such changes is the increase of the
phosphate concentration by continuous introduction with
the feed. The phosphate increase to values above 10 - 20
mg/1 is disadvantageous since the undesired algal growth
is promoted by phosphate.
The following measures are known for the phosphate
reduction:
a) Binding of phosphate to A13+ and/or Fe3+ oxides
(hydroxide group-containing granulates) which are
introduced into the filter system. Disadvantageous
is their limited capacity. After their exhaustion,
it is necessary to change the granulates, which is
frequently very laborious. If the aquarianist does
not regularly measure the phosphate content, he will
not recognise the exhaustion of the material and the
P033- concentration in the maintenance water will
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again increase, i.e. the treatment success of this
method is frequently only insufficient.
b) In the case of regular use, the addition of
dissolved inorganic A13 and/or Fe3+ salts also leads
to a lowering of the P043- concentration.
Disadvantages of this process are:
- high fish toxicity of the dissolved inorganic A13+
and Fe3+ salts,
- enrichment of the water with anions, such as e.g.
chloride and sulphate,
- reduction of the carbonate hardness, of the HCO3-
and C032- content and thus
- reduction of the buffer capacity,
- lowering of the pH level and danger of the acid
fall at KH = 00 dH,
- turbidity of the water and unpleasant flocculation
of A1(OH)3 and FE(OH)3.
B) A further example for the said undesired changes is the
increase of the nitrate concentration by continuous
introduction of proteins and other sources of nitrogen
with the feed. All sources of nitrogen originating from
the feed, to the greater part proteins, are oxidised
microbially via ammonia and nitrite to nitrate. The
continuous nitrite increase represents an unnatural
loading of the maintenance water which is undesired for
the aquarianist. Frequently, the nitrate content of the
starting water is already so high, e.g. at 25 - 50 mg/1,
so that the natural NO3- concentration of a few mg/1 is
never achievable by change of water.
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The following measures are known for the lowering of the
nitrate content:
a) Lowering of the nitrate content by anion exchangers,
mostly in chloride form. Disadvantageous is hereby
the replacement of the nitrate ions by the loading
anions of the exchanger, mostly chloride, and the
replacement of sulphate and hydrogen carbonate ions.
Besides the undesired lowering of the carbonate
hardness, the chemical water composition is
completely changed.
b) Denitrification in anaerobic medium or in anaerobic
reactors. By introduction of practically insoluble,
biologically decomposable organic, nitrogen-free
material in granulate form into the filter system,
by means of strong 02 consumption anaerobic regions
are provided in which nitrate, as source of oxygen,
is reduced to N2. Disadvantageous is:
- the uncertain dosing,
- the uncertain process control and process
controlability,
- the sulphate reduction to be expected in the case
of small NO3- concentrations to highly toxic
hydrogen sulphide.
C) The lowering of the carbonate hardness caused by
nitrification forms a further example for the mentioned
undesired water changes. The oxidation of the continuously
supplied organic nitrogen proceeds via the oxidation of
ammonia to nitrite made possible by nitrifying bacteria.
In the case of this biological process, one mol H-4 ions
CA 02382949 2002-02-21
result per mol of ammonia. The liberated 11+ ions react
with bases present, mostly hydrogen carbonate as former of
the carbonate hardness, with protonisation and reduction
of the carbonate hardness.
For the compensation of the carbonate hardness losses (or
HCO3- losses) but also for the increasing of the carbonate
hardness, the following measures are known:
a) Addition of NaHCO3 and/or Na2CO3 as powder or as
solution. The process functions dependably but
involves the following disadvantages:
- In the case of NaHCO3/Na2CO3 mixtures, it results
in rapid pH increases in the maintenance water
which lead to considerable stress of the
organisms.
- In waters with increased ammonium contents,
parallel to the pH increase inter alia a lethal
amount of ammonia is liberated.
- The water solubility of NaHCO3 is relatively low so
that highly concentrated liquid products with
convenient use are not possible.
b) Addition of freshly prepared solutions which,
besides dissolved calcium hydrogen carbonate, also
contain much free CO2. The excess CO2 can lead to a
rapid CO2 damaging of the organisms. Besides the HCO3
concentration, the Ca2+ concentration is here also
increased, which is not always desired.
Furthermore, chemically and biologically caused losses of
dissolved calcium hydrogen carbonate can bring about
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undesired water changes. Due to CO2 consumption and the pH
increase connected therewith, the lime/carbonic acid
equilibrium is displaced in the direction of lime
precipitation. The disadvantageous loss of dissolved
Ca(HCO3)2 leads to a corresponding lowering of the calcium
concentration and of the HCO3 concentration (carbonate
hardness lowering).
For the compensation of the losses of Ca(HCO3)2 or its
increasing, the following measures are known:
a) Addition of solutions which, besides Ca(HCO3)2 still
contain free CO2. This measure is encumbered with the
above-described disadvantages. A further disadvantage
lies in the laboriousness of the process since the
Ca(HCO3)2 solutions must be laboriously prepared by
dissolving of CaCO3 or Ca(OH)2 in CO2-enriched water. By
addition of Mg(OH)2 or MgC030MG(OH)2 a solution can also
be prepared which contains additional Mg(HCO3)2.
b) Addition of solid mixtures which contain equivalent
amounts of NaHCO3 and soluble Ca, Mg salts (mostly
chlorides). By dissolving of these mixtures in
maintenance water, the ions Ca2+ + 2 Cl- + 2 Na+ + 2 HCO3-
are introduced. Besides the desired [Ca2+ + 2 HCO3], the
water now contains the equivalent amount of NaC1 (or
also Na2SO4), which is undesired. The disadvantage of
this process consists in the introduction of foreign
salts, e.g. NaC1 or Na2SO4.
Finally, a consumption of dissolved carbon dioxide also
changes the water quality.
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Algae, water plants and autotrophic microorganisms
continuously require dissolved carbon dioxide. Besides
the pH value thereby increased, a CO2 deficiency situation
also results which acts disadvantageously on chemical and
biological processes.
For the compensation of the CO2 deficiency, the following
CO2 addition measures are known:
a) Addition of CO2 gas from CO2 pressure bottles.
Problematical in the case of this method are:
- the difficultly adjustable and controllable dosing,
- the price,
- the safety risks which are involved with the pressure
gas system,
b) CO2 production by anodic oxidation of a graphite
electrode. The system contains the following
disadvantages:
- poor dosability,
- CO2 peaks due to secondary chemical processes on the
cathode, involved with a strong decalcification,
- formation of oxyhydrogen gas,
- formation of chlorine in chloride-enriched waters.
c) Production of CO2 in external formation reactors. Here,
too, serious, system-caused disadvantages exist, e.g.
- strong temperature dependency of the fermentation
process,
- difficultly controllable.process,
- very poor dosing possibility and dosing constancy.
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The various described problems initially appear to be
heterogenous and not solvable with one principle.
Surprisingly, however, for all partial problems there
exists a common solution which includes the following
chemical and microbiological principles:
- Utilisation of the microbiological activity of the
water and especially of the filter systems in the
maintenance systems which include the aerobic and
anaerobic processes.
- Use of components, products and compositions which are
biologically decomposable in part or completely.
- Linkage of microbiological and chemical processes in
the maintenance system.
- Use of components, products and compositions which not
only fulfil the desired function but introduce no
undesired additional materials or allow them to
accumulate.
- Use of components, products and compositions which are
completely safe for fish and other aquatic organisms.
- All products and methods behave ecologically neutral
and lead to no secondary impairments of the water
quality.
- All promoting functions are alone very simple to handle
and make possible dosed water additions.
Thus, the subject of the invention is a process for the
improvement of the water quality of biological
maintenance systems, which is characterised in that to
the maintenance system one adds singly or in combination
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9
a) for the lowering of the phosphate concentration, at
least one easily or sparingly soluble A13+, Fe3+,
ZrO2+ or Ca2+ salt of an organic carboxylic acid,
possibly in admixture with an organic carboxylic acid;
b) for the lowering of the nitrate concentration or
limitation of the nitrate increase, at least one water-
soluble N-free, biologically decomposable organic
compound;
c) for the increasing of the carbonate hardness or of the
HCO3- concentration, at least one alkali metal or
alkaline earth metal salt of an organic acid;
d) for the increasing of the total hardness or of the
concentration of Ca2+ and Mg2+ hydrogen carbonates, a
mixture of at least one Ca2+ and Mg2+ salt of an organic
carboxyiic acid and for the increasing of the CO2
concentration, at least one biologically decomposable
compound.
Furthermore, the subject of the invention is a single or
multiple component product for the improvement of the water
quality of maintenance systems for the functional, causal use
according to need, characterised by a content (singly or in
combination) of
1.) at least one easily or sparingly soluble A13+, Fe3+, TiO2,
ZrO2+ or Ca2+ salt of an organic carboxylic acid, possibly
in admixture with an organic carboxylic acid;
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2.) at least one water-soluble, N-free biologically decomposable organic
compound;
3.) at least one soluble alkali metal or alkaline earth metal salt of an
organic
carboxylic acid, and
4.) a mixture of at least one Mg2+ and Ca2+ salt of an organic carboxylic
acid.
5 The consistent use and linking of the maintenance system as
microbiological and
chemical reactors for the achievement of the desired water improvement from
simple
added precursors is novel and also not obvious for the expert and, because of
the
simplicity, of the controllable and commanding processes and of the complete
absence of potentially damaging side effects and actions, brings considerable
and
10 innovative advantages in comparison with the solutions of the prior art.
An especial
advantage of the invention is also to be seen in the fact that it makes
possible a
separate or common solution of the described partial problems.
According to another aspect of the present invention, there is provided a use
of at
least one easily or sparingly soluble Al3+-, Fe3+-, ZrO2- or Ca2+-acetate,
-formate, -tartrate and/or -citrate for lowering of the phosphate
concentration of the
water of biological maintenance systems.
According to still another aspect of the present invention, there is provided
a process
for the improvement of the water quality of biological maintenance systems by
using
the microbiological activity in said biological maintenance systems, wherein
one adds
to the maintenance system in combination a) for the lowering of the phosphate
concentration, at least one easily or sparingly soluble Al3+-, Fe3+-, TiO2-,
ZrO2- or
Ca2tacetate, -formate, -tartrate and/or -citrate; b) for the lowering of the
nitrate
concentration or limitation of the nitrate increase, at least one water-
soluble N-free,
biologically decomposable organic compound; c) for the increasing of the
carbonate
hardness or of the HCO3" concentration, at least one alkali metal or alkaline
earth
metal salt of a carboxylic acid; d) for the increasing of the total hardness
or of the
concentration of Ca2+ and Mg2+ hydrogen carbonate, a mixture of at least one
Ca2+
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10a
and Mg2+ salt of an organic carboxylic acid; and e) for the increasing of the
CO2
concentration, at least one biologically decomposable compound.
According to yet another aspect of the present invention, there is provided
multiple
component product for the improvement of the water quality of biological
maintenance systems by using the microbiological activity in said biological
maintenance systems comprising, in combination, 1) at least one easily or
sparingly
soluble Al3+-, Fe3+-, TiO2-, ZrO2- or Ca2+-acetate, -formate, -tartrate and/or
-citrate;
2) at least one water-soluble, N-free biologically decomposable organic
compound;
3) at least one alkali metal or alkaline earth metal salt of an organic
carboxylic acid;
and 4) a mixture of at least one Mg2+ and Ca2+ salt of an organic carboxylic
acid.
In the following, the detailed solutions according to the invention are
described:
A) Lowering of the phosphate concentrations
This preferably takes place with salts of Al3+, Fe3+ and TiO2+ or ZrO2+ with
organic
carboxylic acids, e.g. with their acetates, formates, tartrates and especially
citrates.
Besides the strongly phosphate-binding metal ions Al3+, Fe3+, TiO2, ZrO2,
there can
also be used calcium salts of organic carboxylic acids in similar manner,
however
with considerably
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smaller phosphate elimination ability. Mixtures of salts of
organic acids with the basic organic acids and other organic
acids are also usable with the same effect, e.g.
aluminium citrate plus citric acid,
iron (III) citrate plus citric acid,
iron (III) citrate plus tartaric acid.
Furthermore, it is also possible to add sparingly-soluble
salts of the said metals with organic acids in solid form
(powder, granulate, tablets) as depot phosphate eliminators
to the filter system or generally to the maintenance system.
The principle is illustrated in the following for A13+ and
Fe3+ salts but applies correspondingly also for TiO2+ and ZrO2
salts. If A13 and/or Fe3+ salts of carboxylic acids are added
to the maintenance water, initially no flocculation and
turbidity is observed. Only in the case of aerobic biological
decomposition in the filter system according to
aluminium citrate (A13+) + 3HCO3-
aerobic decomposition
iron (III) citrate (Fe3+) + CO2
In the case of direct subsequent formation of A1(OH)3 or
Fe(OH)3 according to
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Fe3+ (Fe (OH) 3)
+ 3HCO3 _____________________________ > + 3CO2
A13+ (A1(OH)3)
is phosphate added on and precipitated out together with the
hydroxides.
The metal hydroxides precipitated out with co-flocculated
phosphate collect in the filter sludge and are eliminated in
the case of the regular filter cleaning.
By means of regular addition of organic metal salts, e.g. as
aqueous solution, to the maintenance water, the phosphate
increase can be completely prevented.
In contradistinction to the phosphate precipitation with
inorganic A13+ or Fe3+ salts, the phosphate precipitation
according to the invention contains serious and surprising
advantages:
- no turbidity and flock formation results in the water,
- the process takes place substantially in the biologically-
active filter system,
- the organic metal salts behave
toxicologically neutral,
ecologically neutral,
carbonate hardness neutral,
- no enriching foreign ions are added,
- by aerobic decomposition of carboxylic acid anions, only
CO2 is produced, which positively influences the CO2
content or compensates the CO2 consumption in part.
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The resulting phosphate concentrations are typical for each
metal:
for Fe citrate: about 0.0 - 0.2 mg/1,
for Al citrate: about 0.0 - 0.5 mg/1,
for Ca citrate: about 0.5 - 1.5 mg/l.
Very good phosphate elimination successes are achieved when,
weekly or two weekly; 1 mg/1 to 100 mg/1, preferably 10 mg/1
to 40 mg/1 aluminium citrate, iron citrate or their mixtures
are added to the maintenance water. The phosphate elimination
action is dependent upon the introduced amount of metal
cation.
B) Lowering of the nitrate concentration or limitation of
the NO3 increase by N-free, soluble organic compounds.
If N-free, organic, decomposable substances are added
regularly to the maintenance water, also without the presence
of anaerobic reactors, the increase of the nitrate
concentration is slowed down or limited and a nitrate
concentration is achieved which levels out at an average
level. Without treatment with these water additives according
to the invention, the nitrate content increases ever further
monotonously and unlimitedly. Since the reason for the
hindered or limited nitrate increase lies in a partial
denitrification in the anaerobic microregions in the filter,
parallel to the slowing down, limitation of the nitrate
increases, the nitrification-caused loss of carbonate
hardness (HCO3- concentration) is also inhibited or limited.
As nitrate-reducing, water-soluble compounds, in principle
all biologically decomposable organic compounds can be used
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but preferably aliphatic compounds, such as for example
alcohols; e.g. glycerol, sorbitol, ethanol, sugars, e.g.
pentoses, hexoses, saccharose, carboxylic acids, e.g. acetic
Acid, citric acid, lactic acid and tartaric acid.
Combinations of in each case equal part amounts of citric
acid and saccharose or acetic acid and saccharose have also
proved to be very useful.
If, to the maintenance water, one adds three times a week or
every two days 5 100 mg/1, preferably 5 - 40 mg/1 of the acid
compounds or mixtures, then the nitrate increase is slowed
down and, in relation to the selected dosing, definite
nitrate highest concentrations are no longer exceeded.
Dosing examples for the combination citric acid/saccharose
are:
a) 3 dosings per week with 10 mg/1 (citric acid plus
saccharose (1:1)]: nitrate limiting concentration: 60 -
80 mg/1
b) 3 dosings per week with 20 mg/1 [citric acid plus
saccharose (1:11]: 40 mg/l.
In the case of higher dosings, e.g. 60 - 100 mg/1 three times
weekly or more frequent lower dosings, e.g. daily 10 mg/1,
the nitrate limitating concentration can be lowered still
further, e.g. to 5 - 10 mg/1 NO3-.
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Parallel to the NO3- stabilisation, there is also achieved a
stabilisation of the carbonate hardness at minimum values
below which the carbonate hardness does not sink furter.
The added compounds are completely broken down to H20 and
CO2. The CO2 formed is used by plants, algae and nitrifying
bacteria as C-source.
By introduction of an aeration, the CO2 concentration, can be
corrected downwardly according to need.
C) Increasing of the carbonate hardness or of the HCO3-
concentration
In the case of the solution according to the present
invention, one makes use of the following
microbiological/chemical principle with the use of Na, Ca2+,
Mg2+ and Sr2+ salts of aliphatic carboxylic acids, such as
e.g. acetic acid, lactic acid, citric acid, tartaric acid,
formic acid, propionic acid, malic acid and the like.
If carboxylic acids, e.g. acetic acid, are decomposed
microbiologically, there results only H20 and CO2:
02, decomposition
CH3COOH ____________________ > 2CO2 + 2H20
If, on the other hand, one subjects salts of the carboxylic
acids to the microbiological decomposition, then, besides CO2
corresponding to the number of the introduced negative
charges of the anions, hydrogen carbonate is also formed:
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02, decomposition
CH3C00- CO2 + 1, 5 H20 + HCO3-
.
By the introduction of salts of carboxylic acids into the
maintenance water, after biological decomposition, the
hydrogen carbonates are formed.
On the example for sodium hydrogen carbonate from organic
sodium salts, e.g. Na acetate, Na citrate, this may not act
very spectacularly since NaHCO3 itself is easily accessible.
However, even here, in the case of liquid composition, the
great advantage exists of the mostly - in comparison with
NaHCO3 - very high solubility, for example Na acetate which
permit high product concentrations and ranges.
A further advantage of the use of organic Na salts instead of
NaHCO3 or Na2CO3 consists in the pH neutral use:
- The Na salt of organic acids acts pH neutral, with excess
carboxylid acid(s) can even be adjusted acidic in the
product. This is naturally not possible with NaHCO3 or
Na2CO3.
- In the case of biological decomposition (apart from in the
case of formates), CO2 still results which also counters a
pH increase.
The advantages of the problem solution according to the
invention are still better recognisable when one considers
the introduction of the hydrogen carbonates of the alkaline
earth metal, Mg2+, Ca2+, Sr2+ which, as known, are not
available as substances. By addition of the soluble Mg2+,
Ca2+, Sr2+ salts of organic carboxylic acids, the desired
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concentrations of the hydrogen carbonates can be built up in
the maintenance water without problems.
Example: (acetate)
02, decomposition
M2+ (OAC) 2 ___________________ >
742+ LAJ
cur."-, A 3 J 2 -r 2
...).uts
21/4./
m2+ mg2+, Ca2+, Sr2+
The dosing is orientated to the desired adjustment or
increase of the carbonate hardness or of the HCO3-
concentration. 1 mMo1/1 Na salt of organic carboxylic acids
increases the carbonate hardness by 2.8 dH, 1 mmo1/1 Mg2+,
Ca2+, Sr2+ salts of organic carboxylic acids increases the
carbonate hardness by 5.6 dH.
The alkali metal or alkaline earth metal salts of the organic
carboxylic acids can be added to the maintenance water in
solid form (powder, granulate, tablets) or in the form of
aqueous solutions.
As carboxylic acids, there can be used:
a) for Na + salts:
practically all aliphatic carboxylic acids, especially
acetic acid, lactic acid, citric acid, tartaric acid and
the like.
b) for Mg2+ salts:
practically all aliphatic carboxylic acids, especially
acetic acid, lactic acid, citric acid, tartaric acid and
the like.
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c) for Ca2+ salts:
all aliphatic carboxylic acids which form water-soluble
Ca2+ salts, especially formic acid, acetic acid,
propionic acid, lactic acid, malic acid and the like.
d) for Sr2+ salts:
all aliphatic carboxylic acids which form water-soluble
Sr2+ salts, especially formic acid, acetic acid,
propionic acid, lactic acid, malic acid and the like.
D) Increasing of the total hardness or of the concentration
of Ca2+ and Mg2+ hydrogen carbonates
The principle of this problem solution according to the
invention and all important details of use were described
under C). The advantages of the method and of the composition
are:
- very simple and sure, defined adjustment and increase of
the total hardness,
- problem-free preparation and use of product compositions,
especially liquid solutions,
- no introduction of undesired foreign ions,
- easy adjustment of all desired Mg:Ca ratios from co:1 to
1:00.
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- only controlled amounts of CO2 are produced which serve for
the C-supply for plants, algae and autotrophic micro-
organisms.
- besides the here-described Mg2+ and Ca2+ hydrogen carbonates
formed from organic salts, other inorganic Mg2+, Ca2+ salts,
such as e.g. chlorides or sulphates, can also be added in
combination so that every possible or required chemical
composition of the total hardness can be realised.
E) Increasing of the CO2 concentration
In the preceding problem solutions A) to D), it has already
been described that, In the case of the biological breakdown
of organic compounds, CO2 is formed in the maintenance
system. This can be built up to an internal,
microbiologically-working CO2 supply system. A continuous and
sufficient but still not organism-damaging supply of CO2 to
the maintenance water fulfils various important functions:
- carbon fertilising of the plant organisms,
- carbon supplying of the autotrophic micro-organisms,
especially of the nitrificants,
- prevention of the pH increase caused by CO2 consumption,
- adjustment of a definite pH value by adjustment of the
HCO3-/CO2 acid-base equilibrium,
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- intervention in the lime/CO2 equilibrium and prevention of
the chemical and biological lime precipitation.
It has been shown that CO2 concentrations between 1 and 25
mg/1, preferably 5 - 15 mg/1, lie in the optimum range.
Potential CO2 damagings of fish and other water organisms do
not occur here. Since CO2 is continuously used up in the
maintenance system and losses emerge into the atmosphere, CO2
must be dosed in the correct amount to the maintenance water.
This can be achieved very easily by a daily or every two day
dosing to be carried out of biologically decomposable organic
compounds, e.g. of aliphatic organic carboxylic acids,
alcohols and sugars. The following compounds have proved to
be especially useful:
a) carboxylic acids: formic acid, oxalic acid, acetic acid,
lactic acid, citric acid, malic acid, tartaric acid,
b) alcohols: ethanol, glycerol, sorbitol,
c) sugars: pentoses, hexoses, saccharose.
If one doses the carboxylic acids alone, then, in a chemical
reaction, from the hydrogen carbonate supply, the equivalent
CO2 amount is immediately liberated:
HCO3- + CH3COOH CO2 + H20 + CH3C00-
In the case of the subsequent biological breakdown of the
carboxylic acid anion, the consumed hydrogen carbonate is
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slowly again produced (within a few hours up to 24 hours) and
further CO2 formed:
CH3C00- ________________________ > HCO3- + CO2 + 1 = 5 H20
Consequently, carboxylic acids produce CO2 in a stepped
process:
a) in a secondary reaction by,protonisation of HCO3-,
b) in a reaction lasting a few hours up to 24 hours by
oxidative biological breakdown.
Alcohols and sugars added to the maintenance system are
subsequently broken down to H20 and CO2 in a relatively slow
microbiological reaction.
By choice of combinations of different C-sources with
different speeds of the CO2 liberation, a very uniform CO2
introduction can be achieved, e.g. by the combination of
citric acid and saccharose or acetic acid and saccharose. The
individual compounds or combinations are dosed as follows:
daily 1 - 20 mg/1, preferably 3 - 10 mg/1 or also every 2
days 2 - 40 mg/1, preferably 6 - 20 mg/l.
The water improvement agent according to the invention can be
used for the individually defined function purposes of use in
all biological maintenance systems, such as e.g.
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- aquaria (warm water, cold water, fresh water, salt
water),
- garden ponds, koi ponds,
- aquaterrains,
- large aquaria (zoos, public aquaria).
The agent according to the invention is made available in the
form of individual component products or a multiple component
product, e.g. as packing for 100 to 1000 1 of maintenance
system, preferably as aqueous concentrate. The individual
components 1.) to 4.) in the concentrate can hereby be
combined in the amounts corresponding to the previously
mentioned dosage recommendations. However, the individual
components can also be packed individually or in compatible
mixture in the single dose corresponding to the dosage amount
or in larger amounts in solid form, e.g. as powder,
granulates, extrudates, pearls, capsules or in tablet or
liquid form. In this form, the individual partial problems
can be solved individually or in any desired combination by
addition of individual components or mixtures. Exact
statements about the dosing of the concentrate individual
components or mixtures are to be found in the packaging or on
the leaflet in the packaging.
The dosing frequency is given from the functional use. It
extends from daily over every two days and once or twice a
week to once per two weeks or according to need.
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Additional treatments in the case of use of the products
according to the invention:
Since, in the case of the described mostly oxidative
breakdown processes, the amount of oxygen necessary for the
complete breakdown is used up, expediently, besides the use
of the water treatment agent according to the invention, an
additional treatment is carried out. Thus, it can be
necessary - since the oxygen of the maintenance water
standing in equilibrium with the atmosphere is limited to
about 8 - 10 mg/1 (15 - 25 C) - to,introduce oxygen during
the water treatment in order not to bring about an 02
deficiency situation.
By means of permanent mild fine-bubble aeration or addition
of an amount of hydrogen peroxide equivalent to the 02
requirement, the described water treatment is also oxygen-
neutral and thus environmentally neutral.
