Hanna Instruments

HI-764 Ultra Low Range Nitrite Checker

Sorry, currently out of stock

Click here to be notified by email when HI-764 Ultra Low Range Nitrite Checker becomes available.

Nitrification is the biological oxidation of ammonia (ammonium ion) into nitrite followed by the oxidation of the nitrites to nitrates. The first step of this 2-step process is carried out in an aquarium by nitrifying bacteria. During this quick process, the ammonium levels drop while the nitrite levels increase. Since nitrite is just as harmful as ammonia, nitrite levels should be maintained at immeasurable levels. A mature biological filter should be able to keep nitrite levels low.

The HI764 Checker® Handheld Colorimeter bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits are not very accurate, while professional instrumentation can cost hundreds of dollars and can be time-consuming to calibrate and maintain. Hanna Checker®’s are accurate, affordable and easy to use.

To begin measurements, first, zero the instrument with your water sample. Next, add the reagent. Last, place the vial into the Checker®, press the button and read the results. It’s that easy.

Features at-a-glance:

  • Reads in parts per billion nitrogen-nitrite (NO2 -N)
  • Great for new aquariums
  • Saltwater only
  • comes with 6 tests, reagent refill for 25 tests: HI764-25

 Extra reagent can be found here



0 to 200 ppb


1 ppb

Accuracy @ 25°C/77°F

±10 ppb ±4% of reading

Light Source

LED @ 525 nm

Light Detector

silicon photocell


adaptation of the EPA Diazotization method 354.1


0 to 50°C (32 to 122°F); RH max 95% non-condensing

Battery Type

(1) 1.5V AAA


after two minutes of non-use


81.5mm x 61mm x 37.5mm (3.2" x 2.4" x 1.5”)


64 g (2.25 oz.)

Ordering Information

HI764 Checker® is supplied with (2) sample cuvettes with caps, nitrite ULR reagent starter kit for 6 tests (6 powder reagent packets), battery, instructions and quick start guide.


1 year limited warranty