Hanna Instruments Canada
The Hanna Advantage: A Worldwide Leader in Technology and Innovation 100% Quality  360 Value
Contact Hanna: (800) 842-6629
Hanna Instruments Canada
Customer Support: (800) 842-6629

Total Hardness Test Kit Replacement Reagents (100 tests) - HI38033-100


In stock

The HI38033-100 are reagents for the determination of total hardness (as CaCO3) by titration with the HI38033 Total Hardness Chemical Test Kit. There are enough reagents for approximately 100 tests to be used with Hanna’s test kit. These high quality reagents are manufactured in our state-of-the-art facility and are clearly marked with the lot number and expiration date on each packet for traceability.

  • Pre-made reagents for ease of use
  • Prepared with high-purity chemicals
  • Marked with expiration date and lot number for traceability


The HI38033-100 are high-quality reagents that are pre-measured, allowing for users to achieve fast and accurate total hardness measurements with the chemical test kit. These reagents follow the EDTA titration method to determine total hardness concentration as calcium carbonate (CaCO3).

For determination of total hardness, the sample solution is first buffered to pH 10. The calmagite color indicator is added to form weak complexes at this basic pH with magnesium and calcium, forming a red colored complex. Addition of the EDTA titrant solution also forms complexes with the remaining free magnesium and calcium ions. Once all of the free magnesium and calcium ions have been complexed, the excess EDTA preferentially removes the ions bound with the calmagite color indicator, forming a stronger complex. The removal of these metal ions from the indicator causes a color change from red to blue, indicating the endpoint of the titration. The number of milliliters of titrant used to reach the appropriate endpoint will determine the total hardness as mg/L CaCO3. These reagents are designed to be used with samples that have an expected total hardness range of 0 to 30 gpg (grains per gallon) CaCO3.

Additional information

Weight 0.34 kg



SKU HI38033-100
Name Total Hardness Test Kit Replacement Reagents (100 tests) – HI38033-100
Package bottles
Quantity 100 tests
Method EDTA


Total Hardness Test Kit Replacement Reagents (100 tests) – HI38033-100