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HANNA Marine Phosphate ULR Checker HC colorimeter


Designed as a more accurate alternative to chemical test kits, the HI-774 provides quick, accurate results in a few easy steps (see below).


  • Easier to use and more accurate than chemical test kits
  • Dedicated to a single parameter
  • Small size, big convenience
  • Ideal for: Aquariums, Environmental, Aquaculture, Water Quality
  • Tips for an accurate measurement

    It is important that the sample does not contain any debris.

    Whenever the cuvette is placed into the measurement cell, it must be dry outside, and completely free of fingerprints, oil and dirt. Wipe it thoroughly with HI-731318 or a lint–free cloth prior to insertion.

    Shaking the cuvette can generate bubbles, causing higher readings. To obtain accurate measurements, remove bubbles by swirling or be gently tapping the cuvette.

    Do not let the reacted sample stand for too long after reagent is added as accuracy will be affected.

    After the reading, it is important to immediately discard the sample otherwise the glass might become permanently stained.

    Four steps. One click. Instant Readout.

    1. ‘Zero’ the Checker®HC with your vial with 10ml water sample inside

    2. Take the vial out and add your reagent

    3. Place your vial into your Checker®HC

    4. Press the button and read the results

    Battery powered – Allows use away from a power source. Batteries are included with all battery operated products.

    Use HI-774-25 Reagents with HI-774 Phosphate Marine Ultra-Low Range Colorimeter, Checker®HC, 25 Tests.

    Use HI-774-11 Calibration Set with HI-774 Phosphate Marine Ultra-Low Range Colorimeter, Checker®HC.


    Specifications list


    Range 0 to 999 ppb
    Resolution 1 ppb
    Accuracy ±15 ±5% of reading @ 25ºC
    Light Source LED @ 525 nm
    Light Detector Silicon photocell
    Environment 0 to 50°C (32 to 122°F); RH max 95% non-condensing
    Battery Type (1) 1.5V AAA
    Auto-off After 3 minutes of non-use and 2 mins after reading
    Dimensions 86 x 61 x 37.5 mm
    Weight 64 g
    Method Adaptation of Standard Ascorbic Acid Method. The reaction between the phosphate and the reagent causes a blue tint in the sample.