Hanna Instruments HI-93735-0 Total Hardness Colorimetric Reagents, 100 tests
The HI-93735-0 are reagents for low, medium, and high range colorimetric determination of total hardness.
There are enough reagents for 100 tests to be used with Hanna’s HI-96735 Total Hardness EPA Portable Photometer. These high quality reagents are clearly marked with the lot number and expiry date on each packet for traceability.
The HI-93735-0 are high quality reagents that are pre-measured, allowing for users to achieve fast and accurate colorimetric measurements. These reagents follow the EPA recommended method 130.1 in which the reaction between calcium, magnesium, and the reagents causes a red-violet tint in the sample.
Depending on the range of the sample, one of three bottles of reagent A will be used, while reagent B and C are used for all ranges. By simply adding the range-appropriate bottle of liquid reagent A, two drops of reagent B, and the packet of reagent C to the sample, the reaction between calcium and magnesium and the reagents causes a colour change dependent upon concentration.
The intensity of colour is determined by the compatible HI-96735 & HI-97735 photometer and the concentration will be displayed. The results will be displayed in mg/L (ppm) as CaCO3. These reagents are designed to be used with samples that have an expected range of 0 to 250 mg/L, 200 to 500 mg/L, or 400 to 750 mg/L as CaCO3 total hardness.
Tip for an accurate measurement
It is important that the sample does not contain any debris.
When the cuvette is placed into the measurement cell, it must be dry outside and completely free of fingerprints, oil or dirt. Wipe it thoroughly with HI-731318 or a lint-free cloth prior to insertion.
Shaking the cuvette can generate bubbles, causing higher readings. To obtain accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette.
Do not let the reacted sample stand for too long after reagent is added, or accuracy will be lost.
After the reading, it is important to discard the sample immediately, otherwise the glass might become permanently stained.
Specifications
| Package | Bottles & packets |
| Quantity | 100 tests |
| Method | Adaptation of the EPA recommended method 130.1 |
Frequently Asked Questions
Clear answers to help you choose the right water testing solution with confidence
Which brands of water testing kits do you supply?
Do you provide kits for both home and professional use?
Yes — whether you’re a pool or spa owner, aquarium keeper, utility company, or a university laboratory, we have the right solution for your needs.
Can I arrange servicing or calibration for my photometer?
Absolutely. We also provide servicing and calibration to keep your photometers accurate and reliable.
How quickly do you dispatch orders?
Orders placed before 2:30 pm (Monday–Friday) are dispatched the same day. We also ship on Saturdays for your convenience.
Which couriers do you use for delivery?
We deliver through UPS, DPD, and Royal Mail. You can also choose to upgrade to next-day delivery at checkout.
What is your return policy?
We accept returns within 14 days of delivery provided the items are unused, in their original packaging, and in resalable condition. Please contact our team before returning any items.
Can I place bulk or business orders?
Yes, we welcome bulk, trade, and institutional orders. For tailored pricing or large quantities, please get in touch with us directly.
How can I get help if I’m unsure which kit to buy?
You can call us at 📞 +44 (0)115888 2726 and our team will guide you in choosing the most suitable kit for your needs.