Maintain perfectly balanced pool and spa water by accurately measuring Free & Total Chlorine, pH, Alkalinity, and Cyanuric Acid. These essential parameters are crucial for ensuring water safety, preventing biological growth, and optimizing chemical effectiveness.

Chlorine, a powerful disinfectant, exists in forms like hypochlorous acid (HOCl) and hypochlorite (OCl⁻), with HOCl being significantly more effective below pH 7.6. Measuring both free and total chlorine allows you to determine combined chlorine levels, which are responsible for unpleasant odors and irritation.

Alkalinity is vital for water stability, acting as a buffer against pH fluctuations caused by chemical additions like chlorine. Sufficient alkalinity helps maintain a steady pH, preventing rapid shifts that can impact sanitizer efficiency and swimmer comfort.

Cyanuric acid (CYA) stabilizes chlorine, protecting it from degradation by sunlight and extending its lifespan in the pool. Commonly found in dry chlorine products, proper CYA levels are necessary for effective sanitation, though excessive levels can reduce the oxidation-reduction potential (ORP) required to kill bacteria. Therefore, regular CYA measurement is essential for stabilized pools.

Important Note: Direct DPD chemical measurement for chlorine is preferred over ORP readings, as cyanuric acid can mask the true oxidation potential of chlorine and other oxidizers. Even with CYA present, an ORP reading of 625-650 mV can be obtained, but the actual sanitizing power might be diminished.

The Hanna Instruments HI971044 allows any user to measure these critical swimming pool water quality parameters with exceptional, laboratory-grade accuracy. Its pre-made reagents and intuitive tutorial mode guide users step-by-step through each measurement, simplifying complex testing.

Experience superior performance with the HI971044's innovative optical system, ensuring high accuracy, repeatability, and rapid measurement times. This compact, waterproof photometer boasts a user-friendly interface with a backlit dot matrix LED and virtual keys, providing intuitive navigation for selecting units, reviewing GLP data, recalling the last 50 readings, and customizing settings.

Designed for durability and ease of use, the HI971044 is fully waterproof, featuring a cuvette holder with ridges to protect the optical path and a gasketed battery compartment for three standard AA batteries. Its ergonomic design fits comfortably for field use or rests stably on a benchtop, while the large, backlit LCD (71 mm x 37 mm) ensures clear readability in all lighting conditions.

Features & Benefits

• Low-heat LED light source for consistent performance.
• Highly accurate 8 nm narrowband interference filter (+/- 1 nm) with enhanced light efficiency.
• Reference detector modulates LED voltage for stable light output.
• Concave focusing lens minimizes errors from cuvette imperfections.

What's Included with Each Package Option

CAL Check^™ Validation

Verify meter performance and accuracy with advanced features, including CAL Check, which confirms proper operation. Access GLP data for the last calibration, configure setup options, and review all compatible accessories directly on the meter.

Tutorial Mode

Simplify your testing process with the built-in tutorial mode. When activated, this feature provides step-by-step guidance, visually walking you through each stage of the measurement procedure to ensure accurate results.

Method Options

Choose your preferred reagent format for chlorine measurements. The HI971044 offers flexibility with a choice of convenient powder reagents or economical liquid reagents, catering to different testing needs and preferences.

Stable Light Source

Benefit from consistently reliable readings due to the HI971044's internal reference system. This system effectively compensates for any potential light output drifts caused by power fluctuations or changes in ambient temperature, ensuring rapid and stable measurements between your blank and sample.

High Efficiency Light Source

Experience superior performance with LED light sources, which significantly outperform traditional tungsten lamps. LEDs boast higher luminous efficiency, providing more intense light output while consuming less power, and generate minimal heat, contributing to greater electronic stability.

High Quality Filters

Achieve enhanced measurement accuracy with improved optical filters. These high-quality filters ensure greater wavelength precision, allowing the light detector to receive a brighter, stronger signal. The result is superior measurement stability and reduced wavelength-related errors.

Greater Light Yield

Minimize measurement inaccuracies with a precisely engineered focusing lens that efficiently collects all light exiting the cuvette. This innovative design eliminates errors that might arise from imperfections or scratches in the glass, reducing the need for tedious cuvette indexing.