Alkalinity Test Kit

Benchmark™ Alkalinity Test Kit is a simple titration-style test kit for measuring alkalinity in reef aquariums. It is designed to give a clear, repeatable dKH result so you can understand your reef’s carbonate hardness before making dosing adjustments.

What It Measures

This kit measures aquarium alkalinity in dKH. Alkalinity is one of the most important reef water parameters for maintaining stable coral growth, calcium carbonate formation, and overall chemistry balance.

Kit Includes

• Alkalinity titrant
• Indicator bottle
• Benchmark™ test vial
• 1 mL syringe with dispensing tip
• Instruction card

Test Procedure

1. Rinse the test vial with aquarium water.
2. Add 5.00 mL of aquarium water to the vial.
3. Add 1 drop of indicator.
4. Swirl gently. The sample should turn blue.
5. Fill the syringe with alkalinity titrant to 1.00 mL.
6. Add titrant slowly while swirling.
7. Stop at the first stable colour change from blue to red.
8. Record how many mL of titrant were used.
9. Calculate the result using the formula below.

Calculation

Alkalinity dKH = mL titrant used × 10

Example

If you used 0.80 mL of titrant:

0.80 × 10 = 8.0 dKH

Recommended Reef Range

Typical reef aquariums are often maintained around 7.0–9.5 dKH, depending on the system, coral demand, salt mix, and husbandry approach.

Tips for Best Accuracy

• Read the syringe at eye level.
• Swirl continuously as you approach the endpoint.
• Add titrant slowly near the colour change.
• Run a second test if the endpoint was difficult to judge.
• Rinse the vial and syringe with fresh water after testing.

Test first, then dose. Benchmark™ helps reefkeepers make chemistry decisions from measured results instead of guesswork.