Digital Alkalinity Testing Without Guessing Colors

The Hanna Instruments HI772 Marine Alkalinity dKH Checker HC makes one of the most important reef aquarium tests fast, simple, and easy to read.

Designed specifically for saltwater aquariums, the HI772 measures alkalinity directly in dKH and displays the result digitally, eliminating the color matching and interpretation required by traditional test kits.

For reef keepers monitoring alkalinity for coral growth, calcification, dosing, or overall stability, the HI772 is an excellent addition to your regular water-testing routine.

Direct Digital dKH Results

Instead of comparing colors or counting drops and interpreting an endpoint, the HI772 uses a handheld colorimeter to measure the sample and display alkalinity directly in dKH.

Its simple one-button operation makes routine testing quick and repeatable.

Designed for Marine Aquariums

The HI772 measures alkalinity from 0.0 to 20.0 dKH with a resolution of 0.1 dKH.

This range makes it suitable for reef tanks, fish-only saltwater systems, frag tanks, and other marine aquariums where alkalinity stability matters.

Simple Testing Procedure

Fill the cuvette with 10 mL of aquarium water and zero the Checker. Add 1 mL of HI772S reagent, gently mix the sample, return the cuvette to the Checker, and take your reading.

The alkalinity concentration is displayed directly in dKH.

Why Monitor Alkalinity?

Alkalinity is one of the key parameters for maintaining a stable reef aquarium. Consistent alkalinity supports coral calcification and skeletal growth while helping maintain overall water chemistry and pH stability.

Regular testing is especially important in reef systems using two-part dosing, kalkwasser, calcium reactors, or other supplementation methods.

Key Features

• Digital alkalinity measurement in dKH
• Designed specifically for saltwater aquariums
• 0.0 to 20.0 dKH measurement range
• 0.1 dKH resolution
• Accuracy of ±0.3 dKH ±5% of reading at 77°F
• Easy one-button operation
• Large digital display
• Compact handheld design
• Automatic shutoff
• Replaceable AAA battery
• HI772 replacement reagents available separately

Specifications

Model: HI772
Parameter: Marine Alkalinity
Range: 0.0 to 20.0 dKH
Resolution: 0.1 dKH
Accuracy: ±0.3 dKH ±5% of reading at 77°F / 25°C
Light Source: LED at 610 nm
Battery: 1 × 1.5V AAA
Auto Shutoff: After 10 minutes of inactivity

What's Included

• Hanna Instruments HI772 Marine Alkalinity dKH Checker HC
• 2 sample cuvettes with caps
• Reagents for 25 tests
• 1 mL syringe with tip
• AAA battery
• Instruction manual and quick reference guide
• Protective storage case

Why Buy From Infinity and Beyond Aquatics?

Reliable testing makes maintaining a stable aquarium easier. Infinity and Beyond Aquatics carries trusted water-testing equipment for reef keepers who want accurate, repeatable information about their aquarium chemistry.

The Hanna HI772 provides a straightforward digital alkalinity reading, making it easier to track trends and maintain consistent reef parameters.

Shipping

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Orders may ship separately from other products depending on inventory location and availability.

Manufacturer: Hanna Instruments
Model: HI772
For Use With: Saltwater and marine aquariums