The Hanna Marine Alkalinity 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. Professional instrumentation offers greater resolution and accuracy but can cost hundreds of dollars. The Hanna Marine Alkalinity Checker® measures alkalinity in parts per million (ppm) of calcium carbonate (CaCO3) ,using a fixed wavelength LED and silicon photo detector to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.
The HI755 Checker®HC (Handheld Colorimeter) provides a simple, accurate and cost-effective way to measure alkalinity. Crucial in marine environments, alkalinity provides both the carbonate ion required for calcium carbonate skeletal regeneration of coral reefs, as well as a pH buffer against large changes in acidity. Designed as a more accurate alternative to chemical test kits, the HI755 provides quick, accurate results in a few easy steps.
- Range: 0 to 250ppm (mg/L)
- Resolution: 0.1 ppm (mg/L)
- Accuracy: +/- 10% of Reading (0-75) and +/- 5% of reading (75-250)
- Battery Type: 1 - 1.5V AAA
- Alkalinity Checker
- 2 Sample Cuvettes with Caps
- Reagent Start Kit for 25 Tests
The Hanna Alkalinity Checker measures in ppm. In order to convert to DKH:
ppm / 50 x 2.8 = KH
How it works
The Hanna Marine Alkalinity (ppm) Checker® - HI755 makes testing quick and easy.
Press the button to power the meter on. Notice “Add C1” appears on the screen. You are now ready to begin testing.
Fill the cuvette to the 10mL line with sample and fasten the cap.
Using a microfiber cloth, wipe the cuvette to remove any oils or fingerprints from the glass. Then, place the cuvette into the checker and close the lid, making sure it is completely closed. It is important to make sure that the lid is completely closed for an accurate reading.
Press the button. Once the screen shows "Add C2", place the tip on the syringe, and extract 1mL of reagent from the reagent bottle. Once the reagent has been added, cap the cuvette and invert five times to mix.
Wipe the cuvette of any oils and fingerprints, and place back into the meter.
Press the button, and the meter will display the alkalinity in parts per million of calcium carbonate (CaCO3).
Why Test Alkalinity?
Alkalinity is the ability of a system to buffer the pH of a system as acids are introduced. In saltwater systems, alkalinity is present in two main forms; carbonate (CO32-) and bicarbonate (HCO3-) Alkalinity is a critical parameter to check for in aquaculture, especially in reef aquariums where drastic pH swings would be catastrophic to corals. Further, alkalinity is important to the calcification of corals. The ideal range for alkalinity in reef aquariums is between 125-200ppm of calcium carbonate (7-11 dKH). Many test kits are available on the market that rely on a color change that needs to be judged by eye. The HI755 from Hanna makes alkalinity testing easy by simply mixing the sample with reagent and pressing a button.
Product Manuals & Documentation
Hanna Instruments USA Aquarium Supplies
Hanna Instruments is a leading manufacturer of analytical aquarium instrumentation. They were founded in 1978 and are headquartered in Woonsocket, Rhode Island. When Hanna introduced pH Electronic Paper in 1986 it literally revolutionized the world of testing by allowing millions of people in various industries to test for pH in a simple, accurate and affordable way. Hanna employees are constantly challenging themselves to improve on existing technology and to invent new testing techniques with the common goal to simplify analytical testing. This applies not only to instrumentation, but also to sensors development, reagents and chemicals. Hanna also believes in controlling the quality of their products from inception to delivery so they manufacture everything themselves, from meters and electrodes to chemical reagents and buffer solutions.
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