The Durognost SR Threshold Test Kit is a simple set for quickly checking whether water hardness levels fall within the range of 0.25 to 0.5 °dH. Check water hardness quickly Special liquid indicator in a dropper bottle for monitoring residual hardness in softened water, calibrated to the limit values of 0.5 and 0.25 °dH (8.9 and 4.47 ppm). With the Durognost SR kit, you can easily determine whether your water falls within this very soft hardness range. The indicator powder changes colour as soon as the water hardness limit is reached or deviates from it. This gives you a clear result quickly. This set allows for approximately 250 analyses. The kit is only suitable if you wish to check whether the water hardness is very low. If you require exact numerical values, this kit is not suitable. Quick test without laboratory equipment First, rinse the measuring tube with the water sample. Then fill the tube with the water sample up to the 5 ml or 10 ml mark. Add one drop of indicator and mix it thoroughly with the water sample by gently swirling the tube. After approx. 30 seconds, the water sample will change colour. Water sample colour: Green = softened water is fine Red = Regenerate the water softener Please note: When comparing the result with the enclosed table, it is essential to take the selected sample volume (5 ml or 10 ml) into account. Please read the enclosed instructions for use carefully before use.

Duroval TI Test Kit 0-30 °dH from Heyl – Industrial Water Hardness Analysis Titration test kit for determining total water hardness The Duroval TI Test Kit 0-30 °dH is an analysis set for precise determination of total water hardness in water samples via complexometric titration. The TI test kit provides fast and reliable results in the range of 0 to 30 °dH. In approximately 2 minutes, users receive meaningful measurements with an accuracy of 0.5 °dH. Contents of the test kit: Measuring tube Indicator Calibrated dosing pipette 0–30 °dH 30 ml titration solution Reliable Total Hardness Determination via Complexometric Titration The Duroval TI Test Kit 0–30 °dH is a professional analysis set from Heyl for precise determination of total water hardness in industrial and commercial applications. The proven complexometric titration method ensures accurate analysis of raw, process, and operational water across a wide measurement range. The test kit delivers fast and reproducible results. Within approximately 2 minutes, users obtain meaningful measurements with an accuracy of 0.5 °dH, making it ideal for routine checks and commissioning. Advantages of the Duroval TI Test Kit for Industrial Applications The Duroval TI Test Kit stands out due to its simple handling and high measurement reliability. The calibrated dosing pipette ensures precise addition of the titration solution, while the clear color change of the indicator enables accurate evaluation. The compact set is especially suitable for mobile measurements, service tasks, and regular checks in industrial water treatment. It provides a precise manual alternative to automated measurement systems and supports efficient quality and process monitoring. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Refill Pack Reagents for Testoval Iron 0–1 mg/L (II + III) – Original from Heyl Colorimetric reagents for determining dissolved iron in the low concentration range for approx. 100 analyses With the refill pack reagents for Testoval Iron 0–1 mg/L (|| + |||) for the concentration range of 0–1 mg/L Fe, you can replenish your existing Testoval Iron analysis kit with a complete set of chemical reagents for determining iron in water. Original Heyl reagents for precise iron determination in the low measurement range The measurement range covers 0–1 mg/L Fe. Individual values of 0.05 mg/L, 0.1 mg/L, 0.25 mg/L, 0.5 mg/L, 0.75 mg/L, and 1.0 mg/L can be safely read using optical color comparison. As an original Heyl product, the reagents are precisely matched to the Testoval Iron test kit, ensuring consistently reliable results. Advantages of the Original Heyl Refill Reagents for Testoval Iron The refill pack allows for approximately 100 analyses, with a measurement time of about 7 minutes per sample. This makes the set an economical and efficient solution for regular iron analyses in drinking, process, and industrial water. By diluting the water sample at a 1:10 ratio with distilled water, the measurement range can be flexibly extended up to 10 times the iron concentration. Using original Heyl reagents ensures consistently high measurement quality, maximum compatibility, and reliable water analysis. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Testoval pH-Chlor DPD Reagents Refill Pack The Testoval pH-Chlor DPD reagents refill pack is used to supplement an existing Testoval pH-Chlor analysis kit and enables continued fast and reliable manual control of pH value and chlorine content in water. The reagents are specially developed for colorimetric test methods. After adding the reagents, a characteristic color change occurs, which is then evaluated using the color comparison system of the test kit. This allows both the pH value and the concentration of free and total chlorine to be determined easily without electronic measuring devices. The refill pack ensures that existing test kits can continue to be used for routine analyses. Scope of delivery of the Testoval pH-Chlor DPD refill pack from Heyl The set contains all necessary reagents for carrying out further analyses. You receive a complete set of reagents for pH and chlorine determination, sufficient for approx. 70 analyses. The color comparator, cuvette, and other accessories are not included in the refill pack. These can be ordered individually or together as part of the complete test kit via our online shop. Advantages of the pH-Chlor DPD refill pack from Heyl The refill pack is a practical refill solution for the existing Testoval pH-Chlor DPD test kit. It enables the simultaneous determination of pH value as well as free and combined chlorine. It provides fast measurement results within a few minutes. Thanks to the test kit, the analysis can be carried out without electronic measuring devices and can be used independently of location. Possible application areas of the Heyl test kit for pH-chlorine measurement The reagents are suitable for various water analysis applications, such as monitoring water quality in swimming pools and wellness facilities, supervising disinfection processes in water treatment systems, as well as routine checks in technical water systems and service and maintenance operations in the field of water analysis. Technical Data Measurement parameters: pH value and chlorine (free and total chlorine) pH measuring range: pH 6.8 – 8 Chlorine measuring range: 0 – 1 mg/l Readable reference values: pH 6.8 / 7.4 / 8 Chlorine 0.1 / 0.5 / 1 mg/l Number of analyses: approx. 70 Measurement time: approx. 3 minutes Matching products available in our online shop Item number 410601: Testoval pH-Chlor DPD Test Kit – complete test kit for manual water analysis Item number 410603: Replacement Color Comparator pH-Chlor DPD

Testoval Chlor DPD Reagents Refill Pack – Measure Chlorine Levels Reliably Refill your Testoval Chlor test set for consistent results The Testoval Chlor DPD Reagents Refill Pack is designed for DPD chlorine tests in the concentration range of 0.1–1 mg/l for free and total chlorine. Individual values of 0.1 mg/l, 0.2 mg/l, 0.3 mg/l, 0.5 mg/l, 0.75 mg/l, and 1 mg/l can be read using an optical color comparison. With this refill pack, you can continue to perform accurate chlorine determinations. Fast color changes simplify water analysis. Refill Reagents for Precise DPD Chlorine Analysis in the Low Range The Testoval Chlor DPD Reagents Refill Pack from Heyl is intended for refilling the Testoval Chlor test sets and ensures reliable determination of free and total chlorine in the 0.1–1.0 mg/l range. Using optical color comparison, individual values of 0.1 mg/l, 0.2 mg/l, 0.3 mg/l, 0.5 mg/l, 0.75 mg/l, and 1.0 mg/l can be read accurately. This makes the refill pack ideal for routine water monitoring checks. Advantages of the Testoval Chlor DPD Refill Pack for Water Analysis The refill pack allows existing test sets to be used economically and sustainably. The reagents produce fast and clear color changes, simplifying evaluation and reducing measurement errors. The DPD method is a proven procedure for chlorine determination and is suitable for various applications, such as drinking water monitoring, swimming pools, or technical installations. The refill pack ensures consistent measurement quality and reliable chlorine analysis in daily use. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Testoval Phosphate Reagents Refill Pack – Accurate Phosphate Measurement Testoval for continuous, precise phosphate analyses – the original from Heyl Testoval Phosphate Reagents Refill Pack for quick and manual analysis of phosphate content in water. Individual values of 0.25 mg/L, 0.5 mg/L, 1 mg/L, 2.5 mg/L, 5 mg/L, and 10 mg/L can be read using optical color comparison. The refill pack provides reproducible results within minutes. By diluting the water sample at a 1:10 ratio with distilled water, the measurement range can be extended up to ten times. Refill reagents for reliable and reproducible phosphate analyses The Testoval Phosphate Reagents Refill Pack is designed to supplement an existing Testoval Phosphate analysis kit and allows for quick and manual determination of phosphate content in water. The refill pack is ideal for routine monitoring in water analysis. Advantages of the Testoval Phosphate Reagents Refill Pack for water analysis The refill reagents provide reproducible results within minutes and allow for simple evaluation without additional measurement equipment. This supports efficient and reliable phosphate analysis in drinking, process, and industrial water. By diluting the water sample at a 1:10 ratio with distilled water, the measurement range can be flexibly extended up to ten times the phosphate concentration. The refill pack therefore offers high operational reliability and an economical solution for regular phosphate measurements. Using the original Heyl test kit together with the corresponding refill pack ensures consistently reliable and accurate test results. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Testoval Silicate Reagents Refill Pack If the existing test kit is used regularly, the Testoval Silicate reagents refill pack ensures that measurements can continue to be carried out reliably. It is specifically designed for the Testoval silicate system and enables continuous determination of dissolved silicate in water. The included reagents react with the sample and produce a measurable color change. This is then evaluated using the color comparator, allowing the silicate concentration to be determined quickly and transparently – without additional measuring technology. The measuring range is 0–10 mg/l SiO₂ and can be extended by diluting the sample if required. Your advantages with the reagent refill pack from Heyl for silicate measurement The refill pack is a perfectly matched addition for existing Testoval silicate test kits and enables continuous use of the test kit without the need for a new purchase. Thanks to the visual evaluation, no electronic devices are required. Please note that the color comparator and accessories are not included in the refill pack. Also available in our online shop Item number: 410622 Testoval Silicate Test Kit – complete set for analysis Item number: 410624 Replacement Color Comparator

Testoval Iron 0-1 mg/L Test Kit ||/||| - Precise Iron Analysis Rapid iron determination with clear color reaction The Testoval Iron 0-1 mg/L color comparison kit is used to determine the iron content in water within a concentration range of 0-1 mg/L Fe. Individual values of 0.05 mg/L, 0.1 mg/L, 0.25 mg/L, 0.5 mg/L, 0.75 mg/L, and 1 mg/L can be read using an optical color comparison. The kit includes two reagents and a color comparison device for simple concentration determination. The color comparison kit enables reliable detection of low iron concentrations in water. By diluting the water sample at a 1:10 ratio with distilled water, the measurement range can be extended up to ten times. Fast and reliable determination of low iron concentrations in water The test kit is ideal for applications where low iron levels need to be reliably monitored, such as drinking water monitoring, water treatment, or technical installations. Advantages of the Testoval Iron 0-1 mg/L Test Kit The color comparison kit allows for a simple and rapid manual analysis of iron content with a clearly visible color reaction. The included color comparison device supports accurate evaluation and reduces user errors. By diluting the water sample at a 1:10 ratio with distilled water, the measurement range can be flexibly extended up to 10 mg/L Fe. This makes the test kit highly versatile and suitable for both routine checks and extended analyses. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Replacement color comparator without cuvette, for the Testoval Chlorine DPD color comparison kit for the concentration range 0.1–1 mg/l free and total chlorine. The three reagents are not included in the scope of delivery and can be ordered separately or as part of a complete set. Chlorine DPD 0.1–1 mg/l - Color Comparator Testoval – Values by color comparison The Testoval color comparator for Chlorine DPD (0.1–1 mg/l) is a replacement color comparator for the Testoval chlorine test kit from Heyl. It is used to determine free and total chlorine in water by means of an optical color comparison. The device is specifically designed for the measuring range of 0.1 to 1 mg/l chlorine and serves as a replacement part for the corresponding Testoval test kit. The reagents are not included in the scope of delivery and must be ordered separately. Technical data: Analyses: approx. 70 Measurement time: approx. 1 minute The individual values 0.1 mg/l, 0.2 mg/l, 0.3 mg/l, 0.5 mg/l, 0.75 mg/l and 1 mg/l can be read by optical color comparison. Possible applications Drinking water and process water analyses Monitoring of disinfection processes Routine analyses in laboratories Service and maintenance operations in water systems Why should you order the color comparator from Heyl? Fast determination of chlorine content through optical color comparison Specifically designed for Testoval Chlorine DPD 0.1–1 mg/l test kits Clear color scale for quick concentration determination You can also order the test kit complete or as a refill pack: Item number: 410521 Testoval Chlorine DPD reagent refill pack Item number: 410520 Testoval Chlorine DPD 0.1 - 1 mg/l test kit

With the Testoval Chlorine DPD from Heyl, it is possible to obtain visual measurement results within a few minutes. The kit is perfectly suited for water samples in the range of 0.1 to 1 mg/l. Both low-dosed and slightly higher chlorine values within this range can be determined directly. Testoval Chlorine DPD 0.1 - 1 mg/l Test Kit – suitable for fast chlorine measurement The Testoval Chlorine DPD 0.1 1 mg/l test kit is a color comparison analysis set that allows you to visually determine the content of free and total chlorine in water. It covers a measuring range from 0.1 mg/l to 1 mg/l and is suitable for fast, manual water analyses. With this test kit, the amount of chlorine in the water is determined through an optical color comparison. Accordingly, this test kit is ideal for detecting chlorine concentration within a few minutes. Technical details and contents of the test kit Complete color comparison kit Color comparator Reagents A, B and C Measuring spoon Measuring tube Cuvette Approx. 70 measurements possible with the included reagents Measurement time – approx. 1 minute per analysis Why buy the Testoval Chlorine DPD from Heyl? Intuitive measurement via color comparison instead of a digital device Fast results in only ~1 minute Ideal for free and total chlorine in drinking and process water Compact equipment for mobile and fast measurement Possible applications Environment, industry and maintenance Disinfection systems Control of disinfection and cleaning processes Testing chlorine levels in drinking water or process water Refill packs: 1 set of reagents for approx. 70 analyses: Order no. 410521 Replacement color comparator: Order no. 410522

The Testoval Chlor DPD 0.5-4 mg/l is a handy colour comparison test kit for quickly determining the free and total chlorine content in water in the range from 0.5 to 4 mg/l. Within about one minute, you can see how much chlorine is contained in the water. Quickly determine chlorine levels – easily and reliably The test works according to the DPD method. This means that you place a defined amount of water sample in a measuring tube, add the enclosed reagents and compare the resulting colour with the scale included in the delivery. The stronger the colour, the higher the chlorine content. The values 0.5, 1, 1.5, 2, 3 and 4 mg/l can be read directly on the colour scale. Possible uses of the test The test is particularly well suited for reliably checking the chlorine content in water without measuring devices, for example in: Swimming pools and bathing facilities to ensure that the disinfection value is within the optimum range Water treatment or monitoring, when chlorine needs to be checked as an indicator of hygienic water quality As the test works manually by colour comparison, no expensive measuring equipment is required and samples can also be tested on the go. The set includes approx. 70 analyses.

Iron 0–1 mg/l - Color Comparator Testoval - Concentration range 0–1 mg/l Fe The color comparator is a replacement device for the Testoval Iron 0–1 mg/l test kit (II) + (III) from Heyl and is used for the visual determination of iron in water samples. Reagents are not included in the scope of delivery. The Testoval color comparator for iron (0–1 mg/l) is used for the visual determination of iron in water samples. After adding the appropriate reagents, a characteristic color reaction occurs, which is compared with the integrated color scale in the device. This allows the iron concentration to be read quickly and easily. The device is used as a replacement unit for the Testoval iron test kit and enables manual water analysis without electronic measuring devices. By diluting the water sample in a ratio of 1:10 with distilled water, the measuring range can be extended to ten times the concentration. Technical Data Analyses: approx. 100 Measurement time: approx. 7 minutes The individual values 0.05 mg/l, 0.1 mg/l, 0.25 mg/l, 0.5 mg/l, 0.75 mg/l and 1 mg/l can be read by optical color comparison. Possible application areas of the color comparator Thanks to its compact design, it is suitable for both laboratory analyses and mobile on-site measurements. The color comparator is also ideal for monitoring iron in well and groundwater as well as for supervising water treatment systems. Advantages of the Testoval Iron 0–1 mg/l (II) + (III) from Heyl The determination of ferrous and ferric iron is carried out quickly and easily via optical color comparison. The iron content in the water sample can be reliably determined without the use of electronic measuring devices. The scope of delivery includes only a color comparator for simple concentration determination. Replacement reagents & the complete colorimetric test kit are also available in our shop. Item number 410547: Testoval Iron 0–1 mg/l Test Kit (II) + (III) Item number 410548: Refill pack: Reagents for Testoval Iron 0–1 mg/l (II) + (III)

Testoval Phosphate Color Comparison Device – Manual Measurement Replacement color comparison device for quick and easy determination of phosphate in water The Testoval Phosphate Color Comparison Device is designed for fast visual determination of phosphate content in water. Measurement is performed manually via color comparison. Without the use of additional electronic equipment, concentrations from 0.25 mg/L to 10 mg/L P₂O₅ can be read directly using the color scale. The Heyl Testoval is suitable for both routine checks and simple documentation of results. Fast Phosphate Measurement via Color Comparison Without Equipment The Heyl color comparison device is specifically designed for applications requiring fast results and ease of use. By diluting the water sample 1:10 with distilled water, the measurement range can be extended tenfold. With the Testoval Phosphate Color Comparison Device, approximately 180 analyses can be performed, making it an economical solution for routine monitoring. Typical Applications of the Phosphate Color Comparison Device Manual phosphate determination is a proven method in many areas of water analysis, particularly where electronic measurement devices are unavailable or unnecessary. Environmental monitoring Water and wastewater analysis Laboratory applications Advantages of Phosphate Measurement with the Heyl Testoval Kit The Heyl Testoval Phosphate Test Kit offers a reliable, fast, and user-friendly way to determine phosphate content (P₂O₅) in water samples—completely without electronic devices or lab infrastructure. Fast on-site results: The colorimetric measurement provides usable results within minutes, ideal for routine checks, spot measurements, and immediate decisions. Easy handling without equipment: No electronic devices, power supply, or software are needed. Results are read visually via a color scale, making the device robust, error-tolerant, and easy to use. High practicality and mobility: Compact design allows mobile use—in the field, at measurement points, or in operational settings. Perfect where laboratory analysis would be too complex or time-delayed. Accuracy for monitoring and control: Provides practical accuracy for environmental monitoring, water and wastewater analysis, and brewing, allowing limits to be checked and trends detected early. Economical and efficient: With around 180 analyses per kit, the Heyl Testoval offers a cost-effective solution for regular measurements without maintenance, calibration, or follow-up costs for equipment. Extendable measurement range: Simple sample dilution (1:10) allows flexible expansion of the measurement range, increasing usability for higher phosphate concentrations.

Testoval® pH Chlor DPD Test Kit – Color Comparison for pH and Chlorine Quick and reliable determination of pH value and free and total chlorine in water The Testoval pH-Chlor DPD Test Kit is designed for rapid manual analysis of pH and chlorine. The pH measurement range is 6.8–8.0, while the chlorine content is measured in the range of 0–1 mg/L. The values pH 6.8, 7.4, and 8.0 as well as 0.1 mg/L, 0.5 mg/L, and 1.0 mg/L chlorine can be read safely using optical color comparison. Original Heyl Test Kit for Rapid Determination of pH and Chlorine The Testoval® pH-Chlor DPD Test Kit from Heyl is an original color comparison kit for rapid manual analysis of pH and both free and combined (total) chlorine in water. It was specifically developed for the requirements of swimming pool water monitoring. Advantages of the Original Testoval® pH-Chlor DPD Test Kit The Testoval® pH-Chlor DPD Test Kit combines two important water parameters in one set (pH and chlorine), enabling particularly efficient water analysis. With a measurement time of approximately 3 minutes per test, around 70 measurements can be performed – ideal for routine monitoring during operation. As an original Heyl product, the test kit ensures high measurement reliability, reproducible results, and maximum reagent compatibility. It helps operators maintain stable water quality, control disinfection processes, and reliably meet hygienic standards. Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.

Heyl Testoval Phosphate Test Kit – Measure Phosphate Quickly by Hand Colorimetric test kit for easy determination of phosphate (P₂O₅) in water The Heyl Testoval Phosphate Test Kit allows simple and reliable determination of phosphate content (P₂O₅) in water samples. Measurement is performed colorimetrically via a visual color comparison and covers a range of 0 to 10 mg/L. The kit is a practical color comparison set for manual analysis of phosphate in water samples. The color develops within minutes after adding the reagents. By diluting the water sample 1:10 with distilled water, the measurement range can be extended tenfold. The kit allows for approximately 180 analyses in total. Fast Phosphate Analysis in Water Using Color Comparison The colorimetric method enables rapid determination of phosphate without complex equipment. After adding the reagents, the resulting color intensity is compared with a reference scale, allowing direct reading of the phosphate level. Due to its simplicity, the kit is ideal for routine checks, spot measurements, and applications where fast and reliable results are required. Typical Applications of the Phosphate Test Kit Manual phosphate determination is important in many areas of water analysis, particularly where nutrient levels must be monitored. Breweries Environmental monitoring Advantages of Phosphate Measurement with a Heyl Test Kit The Heyl Test Kit provides a simple, fast, and cost-effective way to measure phosphate content in water samples without the need for electronic devices or laboratory infrastructure. The colorimetric method delivers meaningful results within minutes. The main advantage: immediate results, allowing on-site assessment of whether phosphate levels are within acceptable limits, enabling quick response when needed. This is particularly useful for routine checks, spot measurements, or emergency testing. Easy handling: No special training or equipment required Mobility: Ideal for field measurements and decentralized applications Low cost: No purchase or maintenance of electronic devices needed Reliability: Proven method for reproducible results Flexibility: Can be used where no electricity or lab is available Why Phosphate Measurement Is Essential Phosphate is a key nutrient in water, but high concentrations can cause significant ecological and technical problems. Even small excesses can lead to algae growth, oxygen depletion, and deteriorating water quality. Regular phosphate monitoring is critical for: Environmental monitoring: Protect water bodies from over-fertilization Water treatment: Ensure compliance with legal limits Industry & breweries: Maintain stable process and product quality Wastewater management: Monitor the performance of treatment plants The Heyl Phosphate Test Kit enables fast, reliable, and lab-independent monitoring on site, allowing early trend detection and targeted interventions.

Reliable manual determination of dissolved silicate in water Testoval Silicate Test Kit – color comparison for fast analysis The Testoval silicate test kit can be used in many areas, including the early detection of silicate deposits in systems. Silicate can lead to stubborn deposits and reduce the efficiency of systems, which is why regular monitoring is recommended. With the Testoval silicate test kit, the content of dissolved silicate in water can be determined easily and directly on site. The set works according to the principle of visual color comparison and is ideal for applications where fast and traceable results are required without complex measuring technology. It is suitable for the fast, manual analysis of silicate content in water in the concentration range of 0–10 mg/l SiO₂. The individual values 0.25 mg/l, 0.5 mg/l, 1 mg/l, 2.5 mg/l, 5 mg/l and 10 mg/l can be read by optical color comparison. After adding the reagents, the water sample reacts with a characteristic color development. This is then compared with the reference values of the color comparator, allowing the silicate concentration to be reliably estimated. Manual determination of dissolved silicates in water up to 10 mg/l By diluting the sample in a ratio of 1:10, the measurable range can be extended by a factor of 10. With the test kit, approximately 100 individual analyses can be performed. The analysis time is approx. 19 minutes per measurement. Your advantages with the Testoval silicate test kit The Testoval silicate test kit is ideal for the direct determination of dissolved silicate in water. It uses a visual measurement method, meaning no electrical device is required for measurement. The color comparator provides clear gradations for fast reading of values. The test kit is ideal for regular on-site and mobile checks. Application areas of the silicate test kit The test kit can be used in many different areas such as monitoring boiler feed water and steam systems, checking cooling and process water, use in reverse osmosis and treatment systems, as well as routine analyses in laboratories or technical service. The test kit can be used for early detection of deposits and system issues. Why is monitoring silicate in water so important? Dissolved silicates play a crucial role in industrial water treatment, especially in boiler feed water, cooling water, and reverse osmosis systems. Excessive silicate concentrations can lead to the formation of stubborn deposits (silicate scaling), which are difficult to remove and can significantly impair heat transfer and system efficiency. In membrane processes, silicate can also cause irreversible damage and significantly shorten membrane lifespan. Regular monitoring of silicate levels allows early detection of limit values, targeted control of treatment processes, and prevention of costly system damage. The Testoval silicate test kit therefore supports safe process control and long-term operational reliability. Technical Data Measurement parameter: silicate (SiO₂, dissolved) Measuring range: 0–10 mg/l SiO₂ Readable values: 0.25 / 0.5 / 1 / 2.5 / 5 / 10 mg/l Number of analyses: approx. 100 Measurement time: approx. 19 minutes Measurement principle: colorimetric color comparison Additional products available in our online shop Item number: 410623 Testoval silicate reagents refill pack – for approx. 100 additional analyses Frequently asked questions How long do Heyl chemicals last? The shelf life is printed on the label of each product. Upon delivery, the guaranteed shelf life is at least 7 months. Can Heyl reagents also be purchased individually? That depends on the specific item to be ordered. For Testoval products, only the complete refill pack can be ordered. The individual small bottles cannot be reordered separately. For the Duroval test kit, the individual components of the refill pack can also be reordered separately. Can the indicator and titration solution be purchased separately? Yes, this is possible for the Duroval product range. Where can I find the safety data sheet? The safety data sheet can be found directly with the product in our shop or separately in the download area under the relevant heading. How can the chemicals be disposed of? Disposal instructions can be found in section 13 of the safety data sheet. Disposal must be carried out in accordance with official regulations. Can the chemicals still be used after the expiry date? No, the chemicals can no longer be used after the expiry date. After the expiry date, accurate measurement results can no longer be guaranteed. How should Heyl chemicals be stored? Section 7 of the safety data sheet contains all relevant information on the storage of chemicals. The recommended storage temperature should be between 15-25°C.