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Hanna Checker Marine Alkalinity dKH HI772

$55.21 was $ 64.95
Item #
Hanna Instruments
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The Hanna Marine Alkalinity (dKH) 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 absorbance and ion concentration. This level of instrumentation also offers greater resolution and accuracy, but can cost hundreds of dollars. The Hanna Marine Alkalinity 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
Built-in Timer
One Button Operation
The HI772 Checker®HC (Handheld Colorimeter) provides a simple, accurate and cost effective way to measure alkalinity in degrees of calcium hardness, commonly abbreviated as dKH. Critical to marine environments, alkalinity not only provides the carbonate ion required for calcium carbonate skeletal regeneration of coral reefs, but it also acts as a pH buffer against large changes in acidity. Designed as a more accurate alternative to chemical test kits, the HI772 provides quick, accurate results in four easy steps:
Features at-a-glance:
Easier to use and more accurate than chemical test kits
Dedicated to a single parameter
Small size, big convenience
Ideal for: Aquaculture & Aquariums, Water Quality
Range 0.0 to 20.0 dKH
Resolution 0.1 dKH
Accuracy @ 25°C/77°F ±0.3 dKH ±5% of reading
Light Source LED @ 610 nm
Light Detector silicon photocell
Method colorimetric method
Environment 0 to 50°C (32 to 122°F); RH max 95% non-condensing
Battery Type (1) 1.5V AAA
Auto-off after ten minutes of non-use
Dimensions 86.0 mm x 61.0 mm x 37.5 mm (3.4" x 2.4" x 1.5")
Weight 64 g (2.25 oz.)
Ordering Information HI772 Checker® is supplied with (2) sample cuvettes with caps, alkalinity reagent starter kit for 25 tests (1 bottle of alkalinity reagent, 1 ml syringe and tip), ­­­ battery, instructions, and quick start guide.

Customer Reviews

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Great tool to have for testers Dec 28, 2017
I love this thing , not bad pulling out the old testers and check it and gues what closest color it is to get your reading. And takes little time. This thing makes it a breeze even my wife dosent complain when I do my water checks
Life saver for the color blind Dec 22, 2017
I have always had trouble seeing the color change in most other kits. Alk normally is one of the easier ones to register but it still gives me peace of mind. I like to use the Hannah once a week then other kits daily. And the Hannah is always right on what other kits say except it gives me a real number. Couldn’t ask for a better product.
Amazing tester! Mar 19, 2018
One of the quickest and easiest methods of testing one of thr most important reef parameters.
Fast, quick, accurate! Jan 12, 2018
Best Alkalinity tester on the market. I've tried many others, but this one is the simplest, most accurate one out there!
quick and easy Jan 11, 2018
Fast easy and accurate
Best dKH checker on the market Jan 8, 2018
Easy to use, precision quality.

Of all the dKH test kits I have used it really doesn't get much easier than this.
Accurate and Easy! Jan 2, 2018
This is one of the best and fastest methods of testing one of the most important reef tank parameters. The digital dkh reading is accurate and easy to read (have tested against several other titration kits). The hanna alk checker and ulr phosphorus checker are both the easiest and most accurate tests I have in my test kit arsenal!
worth every penny Dec 31, 2017
So worth the cost. Takes the guessing out of testing.
Hannah Checkers Dec 27, 2017
They are so easy to use and really accurate.
Great Product Dec 27, 2017
The Hanna alkalinity DKH checker is the best ALk test I have ever used and also the fastest.
Love this test kit Dec 21, 2017
the hanna alk test is a game changer. I will never go back to reagents. this tool alone helped me figure out the correct kalk dose for my nano.
Works splendid Dec 20, 2017
Love this product, always gives me an accurate reading so i know what i put in my tank.
Fantastic tool Dec 18, 2017
This tool is money well spent. easy to use, accurate.
Great tool for the job! Dec 14, 2017
I use this checker several times per week to monitor the alk in my 2 reef tanks. So quick and easy to keep things in check.
Great! Dec 12, 2017
Consistently accurate and ease of use. What more is needed?
Great! Dec 11, 2017
This is, by far, the easiest to use tester/kit I've ever bought. It takes out the guess work of matching colors.

I, truly, need to get the rest of the line.
Consistent, Accurate, and a must have for daily Alk testing Dec 11, 2017
At some point every advanced SPS hobbyists will begin monitoring Alkalinity on a daily basis to ensure proper dosing of 2-part/kal or to tune a calcium reactor. If you monitor daily or every other day, the Hanna checker has got to be one of best time savers ever. You can get an accurate test done in under a minute and probably under 30 seconds once you've done it a bunch of times. Reagent bottles are only $16 and last for quite a while. I consider it a must have for anyone with SPS/LPS corals that require stable Alk and near daily testing.
Would recommend it Dec 9, 2017
I like taking the guess out of reading the colors of the test. This does a freat job and I think it encourages me to test more. Would but this again.
DKH Dec 8, 2017
This is the easiest way to ck dkh no colors just numbers
Love it. Very Consistent. Jan 15, 2017
I simply love this product. I wish I had made the decision to buy this product earlier. I spent a lot of time with titration tests, figuring out what was the correct end color, getting inconsistent results and not knowing what my Alk really was.

All that is gone for good.

The product is very easy to use. There are 2 steps: 1. Calibrate the unit using your sample water without reagent. 2. Add 10ml of reagent and take your measure. No guesswork.
HI772 Hanna Alkalinity Checker

Hanna Instruments' Kevin Costa comes back to you and discusses the importance of Alkalinity in your aquarium and how to maintain proper levels using the HI772 (dKH) Alkalinity Checker from Hanna Instruments.