Nitrate LR Checker

HI781 Details:

The HI-781 Nitrate Checker HC is a handheld colorimeter that uses the Beer-Lambert principle to determine the concentration of nitrate colorimetrically.

The HI-781 is designed specifically to measure low levels of nitrate in a saltwater aquarium. The 0.00 to 5.00 range is ideal for reef aquarium maintenance.

The Checker®HC handheld colorimeter is supplied with:

• Sample cuvette and cap (2)
• Marine Nitrate Low Range reagent starter kit (reagents for 25 tests)
• Filter paper (25)
• Filter holder (1)
• Mixing vial and cap (1)
• 5 mL syringe with tip (1)
• 10 mL syringe with tip (1)
• 1.5V AAA Alkaline battery (1)
• Instruction manual

Nitrate is a by-product of the Nitrogen cycle. Excessive amounts of Nitrates in a reef aquarium can promote the growth of undesirable organisms including algae and dinoflagellates, while insufficient amounts can lead to starvation in which SPS, and other corals, will show signs including the loss of colour and paleness.

• Ideal for aquariums and marine biology
• Easier to use and more accurate than chemical test kits
• Small size, big convenience

Four steps. One click. Instant Readout.

  1. ‘Zero’ the Checker®HC with your vial & 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

HI781-11 Details:

Each high quality set of standards is manufactured in our state-of-the-art facility and comes supplied with a Certificate of Analysis. The certificate of Analysis provides the lot number, reference values and expiry date to provide traceability when certifying the Checker HC.

Hanna Instruments certifies these standards meet the states tolerance limited indicated.

2.49 ± 0.25 @ 25˚C

These should be used for quality control to validate instrument function on the specified Hanna Instrument only.

Instructions for use:

1 Thoroughly wipe standard cuvette with HI-731318 lint free cloth and only touch the top of the cuvette thereafter. The cuvette wall must be dry and free of smudges.

2 At the c1 prompt place HI-781-11 A standard cuvette into the holder of the checker and press operations button.

3 At the c2 prompt place HI-781-11B standard cuvette into the holder and then press the operations button.

Acceptable results must be between 2.25 and 2.75 ppm @ 25˚C.

HI781-25 Details:

Measurement Procedure

• Press the ON/OFF button to turn the checker on. All segments will be displayed for a few seconds, followed by “Add”, “C.1” with “Press” blinking.
• Using the 10 mL syringe, measure exactly 7 mL of sample into the large mixing vial.
• Using the 5 mL syringe, add exactly 4 mL of HI-781A-0 reagent into the large mixing vial.
• Add the content of one packet of HI-781B-0 reagent into the large mixing vial. Replace the cap and shake vigorously for 1 minute.
• Remove the plunger from the 10 mL syringe. Attach the syringe to the filter holder assembly using the threaded connection.
• Remove the cap from the mixing vial. Hold the syringe and filter holder assembly over a cuvette. Carefully pour the contents of the mixing vial into the back of the syringe.
• Very slowly push the plunger into the 10mL syringe until the 10mL cuvette has been filled up to the 10 mL mark and replace the cap.
• Insert the cuvette into the checker and close the cap.
• Press the ON/OFF button. When the display shows “Add”, “C.2” with “Press” blinking, the checker is zeroed.
• Remove the cuvette, unscrew the cap and add the content of one packet of HI-781C-0 reagent. Replace the cap and shake vigorously for 2 minutes.
• Insert the cuvette into the checker.

Tip 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 or 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 such bubbles by swirling or by gently tapping the cuvette.

Do not let the reacted sample stand for too long after reagent is added, or accuracy will be lost.

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