What is the total hardness measured for?

The total hardness of water is an important parameter for water quality and describes the sum of all alkaline earth ions, mainly calcium (Ca²⁺) and magnesium (Mg²⁺). These ions originate from the natural dissolution of rocks and minerals and have a significant influence on the properties of the water.

In Germany, water hardness is given in °dH (degrees of German hardness):

• 0-7 °dH: Soft water
• 7-14 °dH: Medium hard water
• 14-21 °dH: Hard water
• >21 °dH: Very hard water

Knowing the water hardness is crucial for many applications: from the dosing of detergents and the adjustment of softening systems to the prevention of limescale deposits in pipes, boilers and industrial systems.

Hardness measurement is particularly important for: Drinking water treatment, boiler water monitoring, aquaristics, swimming pools, the food industry and industrial processes.

How does the test set work?

The CALDUR® Total Hardness Test Set GR uses the proven complexometric titration method with EDTA (ethylenediaminetetraacetic acid). In this method, the calcium and magnesium ions are bound by EDTA, with a Reagent indicating the end point by a characteristic color change.

Measuring principle: 1 reagent is added to the water sample. When the titration solution is added drop by drop, the hardness constituents bind to the EDTA. The color change from red to green indicates that all hardness constituents are bound.

Calculation: Each drop of titration solution corresponds to 0.1 °dH (for 5 ml sample) or 0.05 °dH (for 10 ml sample). The number of drops multiplied by the drop value directly results in the total hardness in °dH.

Advantages of the CALDUR® test set

• Quick analysis in just 1 minute

  Ideal for routine checks on site – immediate results without waiting time

• High precision due to drop-by-drop titration

  Measured value per drop: 0.1 / 0.05 °dH – exact results thanks to proven complexometric method

• 100 at 1°dH Determinations per set

  Economical for regular household, commercial and industrial checks

• Clear color change from red to green

  Clear endpoint recognition – easy to read even for inexperienced users

• Flexible sample volume (5 ml or 10 ml)

  Higher accuracy with 10 ml sample due to halved drop value

• Robust, waterproof plastic housing with hinged lid

  Safe transportation and protection of reagents – durable even under harsh conditions

Der Beitrag Caldur® Total hardness GR – Titration erschien zuerst auf RLS Wacon analytics.

What is the total hardness measured for?

The total hardness of water is an important parameter for water quality and describes the sum of all alkaline earth ions, mainly calcium (Ca²⁺) and magnesium (Mg²⁺). These ions originate from the natural dissolution of rocks and minerals and have a significant influence on the properties of the water.

In Germany, water hardness is given in °dH (degrees of German hardness):

• 0-7 °dH: Soft water
• 7-14 °dH: Medium hard water
• 14-21 °dH: Hard water
• >21 °dH: Very hard water

Knowing the water hardness is crucial for many applications: from the dosing of detergents and the adjustment of softening systems to the prevention of limescale deposits in pipes, boilers and industrial systems.

Hardness measurement is particularly important for: Drinking water treatment, boiler water monitoring, aquaristics, swimming pools, the food industry and industrial processes.

How does the test set work?

The CALDUR® Total Hardness Test Set GH uses the proven complexometric titration method with EDTA (ethylenediaminetetraacetic acid). In this method, the calcium and magnesium ions are bound by EDTA, with a Reagent indicating the end point by a characteristic color change.

Measuring principle: 1 reagent is added to the water sample. When the titration solution is added drop by drop, the hardness constituents bind to the EDTA. The color change from red to green indicates that all hardness constituents are bound.

Calculation: Each drop of titration solution corresponds to 0.5 °dH (for 5 ml sample) or 0.25 °dH (for 10 ml sample). The number of drops multiplied by the drop value directly results in the total hardness in °dH.

Advantages of the CALDUR® test set

• Quick analysis in just 1 minute

  Ideal for routine checks on site – immediate results without waiting time

• High precision due to drop-by-drop titration

  Measured value per drop: 0.5 / 0.25 °dH – exact results thanks to proven complexometric method

• 100 at 5°dH Determinations per set

  Economical for regular household, commercial and industrial checks

• Clear color change from red to green

  Clear endpoint recognition – easy to read even for inexperienced users

• Flexible sample volume (5 ml or 10 ml)

  Higher accuracy with 10 ml sample due to halved drop value

• Robust, waterproof plastic housing with hinged lid

  Safe transportation and protection of reagents – durable even under harsh conditions

Der Beitrag Caldur® Total hardness GH – Titration erschien zuerst auf RLS Wacon analytics.

What is the total hardness measured for?

The total hardness of water is an important parameter for water quality and describes the sum of all alkaline earth ions, mainly calcium (Ca²⁺) and magnesium (Mg²⁺). These ions originate from the natural dissolution of rocks and minerals and have a significant influence on the properties of the water.

In Germany, water hardness is given in °dH (degrees of German hardness):

• 0-7 °dH: Soft water
• 7-14 °dH: Medium hard water
• 14-21 °dH: Hard water
• >21 °dH: Very hard water

Knowing the water hardness is crucial for many applications: from the dosing of detergents and the adjustment of softening systems to the prevention of limescale deposits in pipes, boilers and industrial systems.

Hardness measurement is particularly important for: Drinking water treatment, boiler water monitoring, aquaristics, swimming pools, the food industry and industrial processes.

How does the test set work?

The CALDUR® Total Hardness Test Set GHT 100 uses the proven complexometric titration method with EDTA (ethylenediaminetetraacetic acid). In this method, the calcium and magnesium ions are bound by EDTA, with a Reagent indicating the end point by a characteristic color change.

Measuring principle: 2 reagents (Reagent and titration solution) are added to the water sample. When the titration solution is added drop by drop, the hardness constituents bind to the EDTA. The color change from red to green indicates that all hardness constituents are bound.

Calculation: Each drop of titration solution corresponds to 1.0 °dH (for 5 ml sample) or 0.5 °dH (for 10 ml sample). The number of drops multiplied by the drop value directly results in the total hardness in °dH.

Advantages of the CALDUR® test set

• Quick analysis in just 1 minute

  Ideal for routine checks on site – immediate results without waiting time

• High precision due to drop-by-drop titration

  Measured value per drop: 1.0 / 0.5 °dH – exact results thanks to proven complexometric method

• 100 at 10°dH Determinations per set

  Economical for regular household, commercial and industrial checks

• Clear color change from red to green

  Clear endpoint recognition – easy to read even for inexperienced users

• Flexible sample volume (5 ml or 10 ml)

  Higher accuracy with 10 ml sample due to halved drop value

• Robust, waterproof plastic housing with hinged lid

  Safe transportation and protection of reagents – durable even under harsh conditions

Der Beitrag Caldur® Total hardness GHT 100 – Titration erschien zuerst auf RLS Wacon analytics.

What is Sulfite measured for?

Sulfite (SO₃²-) is used in water treatment as an oxygen binding agent to prevent corrosion
in steam boilers, heating systems and closed cooling systems. As a reducing agent
, Sulfite reacts with dissolved oxygen and thus protects pipelines and system components from
oxygen corrosion.

The optimum Sulfite concentration in boiler water is 20-30 mg/l SO₃²-.
Regular monitoring is essential, as values that are too low do not provide sufficient corrosion protection
, while concentrations that are too high are uneconomical and promote the formation of Sulfite.

Sulfite is also used as a preservative and antioxidant in the food industry.
Monitoring the concentration of sulfite is therefore of great importance in various industrial sectors.

How does the test set work?

The CALDUR® Sulfite Test Set – Colorimetric is based on the proven thiobenzoic acid method.
After adding two reagents to the water sample, a
characteristic color develops within 3 minutes, the intensity of which is proportional to the Sulfite concentration.

The measured value is determined by direct color comparison with a supplied 6-level color chart.
Optionally, the sample can also be evaluated photometrically with the WINLAB Data Line photometer.

Advantages of the CALDUR® test set

• Quick analysis in just 3 minutes

  Ideal for regular checks in boiler systems – immediate results on site

• Wide measuring range from 0.5 to 20 mg/l SO₃²-

  Covers the entire practical range for boiler water and industrial applications

• 150 provisions per set – economical in continuous use

  Cost-efficient for daily checks in power plants, heating systems and industrial operations

• Can be used colorimetrically and optionally photometrically

  Flexible for simple on-site tests or precise laboratory analyses with photometer

• Easy handling without special equipment

  No additional technology required – ideal for quick routine checks

• Robust, waterproof plastic housing with hinged lid

  Safe transportation and protection of reagents – durable and reliable even under harsh conditions

Der Beitrag Caldur® Sulfite – Colorimetric erschien zuerst auf RLS Wacon analytics.

What is sulfide measured for?

Sulphide (S²-) is produced by the anaerobic decomposition of organic substances containing sulphur and can cause an unpleasant smell of rotten eggs as hydrogen sulphide (H₂S). Even low concentrations are corrosive and can damage pipelines and structures.

Sulphide is harmful to health in higher concentrations and can cause respiratory and eye irritation in people who work with contaminated water. Sulphide is undesirable in drinking water treatment and must be reliably detected.

In industrial water treatment, in sewage treatment plants and in groundwater samples, sulphide control is essential to prevent corrosion and ensure water quality.

How does the test set work?

The CALDUR® Sulfide Test Set – Photometric is based on the DPD method. After adding two reagents to the water sample, a characteristic coloration develops within 7 minutes, the concentration of which is precisely determined with the WINLAB Data Line photometer.

Advantages of the CALDUR® test set

• Sensitive measuring range 0.05 – 1.0 mg/l S²-

  Detection of even low sulphide concentrations

• 100 provisions per set

  Economical for regular checks

• High precision due to photometric evaluation

  Objective, reproducible measurement results with the WINLAB Data Line

• Proven DPD method

  Reliable results even with stained samples

Der Beitrag Caldur® Sulfide – Photometric erschien zuerst auf RLS Wacon analytics.

What is sulfide measured for?

Sulphide (S²-) is produced by the anaerobic decomposition of organic substances containing sulphur and can cause an unpleasant smell of rotten eggs as hydrogen sulphide (H₂S). Even low concentrations are corrosive and can damage pipelines and structures.

Sulphide is harmful to health in higher concentrations and can cause respiratory and eye irritation in people who work with contaminated water. Sulphide is undesirable in drinking water treatment and must be reliably detected.

In industrial water treatment, in sewage treatment plants and in groundwater samples, sulphide control is essential to prevent corrosion and ensure water quality.

How does the test set work?

The CALDUR® Sulfide Test Set – Colorimetric is based on the DPD method. After adding two reagents to the water sample, a characteristic coloration develops within 7 minutes, the intensity of which is proportional to the sulfide concentration.

Advantages of the CALDUR® test set

• Sensitive measuring range 0.05 – 1.0 mg/l S²-

  Detection of even low sulphide concentrations

• 100 provisions per set

  Economical for regular checks

• Easy handling

  Fast on-site determination without measuring devices

• Proven DPD method

  Reliable and reproducible results

Der Beitrag Caldur® Sulfide – Colorimetric erschien zuerst auf RLS Wacon analytics.

What is sulfate measured for?

Sulphate (SO₄²-) is a naturally occurring anion in many bodies of water and mainly comes from the weathering of sulphate-containing minerals such as gypsum (CaSO₄) and anhydrite. In industrial processes, sulphate also enters the water through wastewater, cooling towers and chemical production processes.

The limit value for sulphate in drinking water is 250 mg/l (Drinking Water Ordinance). Elevated sulphate concentrations can have a deleterious effect and impair the taste of the water. Sulphate monitoring is particularly important in industry, as high concentrations can lead to corrosion of concrete structures and pipelines.

This test kit with a resolution of 20 mg/l SO₄²- per drop is optimized for higher concentrations and enables rapid determination in samples with elevated sulfate content.

How does the test set work?

The CALDUR® Sulfate 20 mg test kit works according to the principle of precipitation titration. A reagent is first added to the water sample. The titration solution is then added drop by drop until a color change indicates the end point.

Measuring principle: Barium ions from the titration solution react with sulphate ions and form poorly soluble barium sulphate. The end point is indicated by a Reagent. Each drop corresponds to 20 mg/l SO₄²-.

Calculation: Number of drops × 20 = sulphate concentration in mg/l.

Advantages of the CALDUR® test set

• Quick analysis in just 2 minutes

  Efficient on-site determination without laboratory equipment

• Measured value 20 mg/l SO₄²- per drop

  Larger measuring range for higher concentrations

• 30 provisions per set

  Economical for regular monitoring

• Proven precipitation titration

  Reliable and reproducible results

• Faster titration at high concentrations

  Fewer drops required than with the 10 mg test set

Der Beitrag Caldur® Sulfate 20 mg – Titrimetric erschien zuerst auf RLS Wacon analytics.

What is sulfate measured for?

Sulphate (SO₄²-) is a naturally occurring anion in many bodies of water and mainly comes from the weathering of sulphate-containing minerals such as gypsum (CaSO₄) and anhydrite. In industrial processes, sulphate also enters the water through wastewater, cooling towers and chemical production processes.

The limit value for sulphate in drinking water is 250 mg/l (Drinking Water Ordinance). Elevated sulphate concentrations can have a deleterious effect and impair the taste of the water. Sulphate monitoring is particularly important in industry, as high concentrations can lead to corrosion of concrete structures and pipelines.

This test set with a resolution of 10 mg/l SO₄²- per drop is ideal for monitoring drinking water, process water and industrial applications in the medium concentration range.

How does the test set work?

The CALDUR® Sulfate 10 mg test kit works according to the principle of precipitation titration. The water sample is first passed through an ion exchanger to remove interfering ions. A reagent is then added and titrated drop by drop until a color change indicates the end point.

Measuring principle: Barium ions from the titration solution react with sulphate ions and form poorly soluble barium sulphate. The end point is indicated by a Reagent. Each drop corresponds to 10 mg/l SO₄²-.

Calculation: Number of drops × 10 = sulphate concentration in mg/l.

Advantages of the CALDUR® test set

• Quick analysis in just 2 minutes

  Efficient on-site determination without laboratory equipment

• Measured value 10 mg/l SO₄²- per drop

  Precise measurement in the medium concentration range

• 30 provisions per set

  Economical for regular monitoring

• Proven precipitation titration

  Reliable and reproducible results

• Ion exchanger for the elimination of impurities

  Precise results even with complex water matrices

Der Beitrag Caldur® Sulfate 10 mg – Titrimetric erschien zuerst auf RLS Wacon analytics.

What is silicate measured for?

Silicate (SiO₂) is a naturally occurring water constituent that comes from the dissolution of rocks and minerals. Silicate is particularly critical in boiler water technology, as it can form glass-like deposits (silicate scale) at high temperatures and pressures, which are extremely difficult to remove.

In high-pressure boilers, the silicate content must be kept particularly low, as even low concentrations can lead to deposits on turbine blades. Typical limit values are 0.02-0.5 mg/l SiO₂ depending on the operating pressure.

Silicate control is also important in drinking water treatment and in the production of ultrapure water (e.g. for the semiconductor industry).

How does the test set work?

The CALDUR® Silicate Test Set – Photometric is based on the molybdate method. After adding three reagents to the water sample, a yellow silicomolybdate complex is formed within 8 minutes, the concentration of which is precisely determined using the WINLAB Data Line photometer.

Advantages of the CALDUR® test set

• Wide measuring range 0.1 – 30 mg/l SiO₂

  Covers the range from boiler water to raw water

• 100 provisions per set

  Economical for regular checks

• High precision due to photometric evaluation

  Objective, reproducible measurement results with the WINLAB Data Line

• Proven molybdate method

  Specific for dissolved silicate

Der Beitrag Caldur® Silicate – Photometric erschien zuerst auf RLS Wacon analytics.

What is silicate measured for?

Silicate (SiO₂) enters the water naturally through the leaching of rocks and soils. Silicate control is particularly critical in boiler water and steam generator treatment: even low concentrations can lead to glass-like deposits on turbine blades and heat exchangers.

In cooling water systems, silicate in combination with calcium and magnesium promotes the formation of deposits that are difficult to dissolve. Regular checks help to avoid costly malfunctions.

Silicate plays a subordinate role in drinking water treatment, but can lead to blockages in membrane filtration processes (reverse osmosis) if the concentration is too high.

How does the test set work?

The CALDUR® silicate test set is based on the silicomolybdate blue method. Silicate reacts with molybdate in an acidic solution to form yellow silicomolybdate, which is then reduced to a blue complex. The blue coloration is proportional to the silicate concentration.

The measured value is determined by direct color comparison with a 6-stage color chart supplied.

Advantages of the CALDUR® test set

• Measuring range 0.25 – 10 mg/l SiO₂

  Covers the practical range for boiler water and industry

• 100 provisions per set

  Economical for regular checks

• Quick analysis in just 1 minute

  Immediate results on site

• Easy handling with 3 reagents

  No measuring devices required

• Robust plastic housing with hinged lid

  Safe transportation and protection of reagents

Der Beitrag Caldur® Silicate – Colorimetric erschien zuerst auf RLS Wacon analytics.