
Hanna Instruments HI-4001-40 Ammonia Filling Solution
HI-4001-40 is a set of 4 x 30 mL bottles of fill solution made specifically for Hanna’s ammonia gas sensing Ion Selective Electrodes (ISEs).
The electrolyte solution should be added to the outer probe body of the HI-4101 ISE before final assembly to ensure optimum performance.
The HI-4001-40 fill solution is a chloride ion-containing electrolyte that is required to provide a reference potential for the HI-4101 ammonia gas sensing Ion Selective Electrode (ISE). As ammonia diffuses through the gas permeable membrane, the thin film of electrolyte on the surface of the pH sensing glass undergoes a pH change. The change in pH of the filling solution is proportional to the concentration of ammonia gas in the solution.
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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.