HI736 Phosphorus ULR Checker HC Colorimeter

HI736 Phosphorus ULR Checker HC Colorimeter

HI736 Phosphorus ULR Checker HC Colorimeter

The Hanna Phosphorus Ultra Low Range (0 to 200 ppb) Checker bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits have limited accuracy and resolution since they rely upon the human eye to discern differences in color. Professional instrumentation incorporates a light source such as an LED or tungsten lamp with a filter and a light sensing detector to precisely determine ion concentration. Professional instrumentation offers greater resolution and accuracy but can cost hundreds of dollars. The Hanna Phosphorus Ultra Low Range Checker uses a fixed wavelength LED and silicon photo detector to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.

Compact, Portable Design

The HI736 Checker HC (Handheld Colorimeter) provides a simple, accurate, and cost-effective way to measure phosphorus in marine systems including reef tanks. Phosphorus is an important parameter to measure in aquaculture and aquariums; levels that are too high can lead to extensive algae growth, depleted dissolved oxygen levels, and ultimately can be fatal to many types of fish and aquatic life. Designed as a more accurate alternative to chemical test kits, the HI736 provides quick, accurate results in four easy steps:

  1. Prepare the sample by following the instructions provided.
  2. Insert the sample into the colorimeter.
  3. Press the button to start the measurement.
  4. Read the phosphorus concentration on the display.


  • Phosphorus Range: 0 to 200 ppb
  • Phosphorus Resolution: 1 ppb
  • Phosphorus Accuracy: ±5 ppb ±5% of reading
  • Phosphorus Method: Adaptation of the Standard Methods for the Examination of Water and Wastewater, 20th edition, Ascorbic-Acid method.
  • Light Source: LED @ 525 nm
  • Light Detector: Silicon photocell
  • Battery Type/Life: (1) 1.5V AAA
  • Automatic Shut-Off: After three minutes of non-use and two minutes after reading
  • Environment: 0 to 50°C (32 to 122°F); RH max 95% non-condensing
  • Weight: 64 g (2.25 oz.)
  • Dimensions: 81.5mm x 61mm x 37.5mm (3.2″ x 2.4″ x 1.5″)

Frequently Asked Questions:

  1. Can the HI736 Checker HC be used in freshwater systems?
  2. No, the HI736 Checker HC is specifically designed for measuring phosphorus in marine systems including reef tanks. For freshwater systems, a different colorimeter should be used.

  3. How often should I test the phosphorus levels in my aquarium?
  4. It is recommended to test the phosphorus levels at least once a week to ensure they are within the optimal range for the health of your marine system.

  5. Can the HI736 Checker HC be used for other water samples?
  6. Yes, the HI736 Checker HC can be used for testing phosphorus levels in other water samples such as lakes, rivers, and ponds. However, it is important to note that the calibration and range of the colorimeter are specifically designed for marine systems.


The HI736 Phosphorus ULR Checker HC Colorimeter is a compact, portable, and affordable solution for accurately measuring phosphorus levels in marine systems. With its easy-to-use design and professional-level accuracy, it provides a reliable tool for aquarists and aquaculture professionals to monitor and maintain optimal phosphorus levels in their systems. Say goodbye to the limitations of chemical test kits and the high cost of professional instrumentation, and say hello to the HI736 Checker HC Colorimeter.