
Hanna Instruments HI-4000-47 pH 4 and 7 Buffer with Chloride Background
HI-4000-47 is a set of pH 4 and pH 7 buffer packets (includes 10 packets of each buffer). These buffer packets contain chloride ions to allow an inner electrode check of the ammonia and carbon dioxide Ion Selective Electrodes.
Before assembling an ammonia or carbon dioxide ISE for the first time, or if reactivating after storage, the inner glass assembly should be conditioned and tested as a pH electrode. The pH buffer packets can be added to 50 mL of deionised or distilled water and the sensor assembly carefully immersed in solution. When the mV measurement in each buffer solution is stable and recorded, the mV difference can be calculated.

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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.
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Absolutely. We also provide servicing and calibration to keep your photometers accurate and reliable.
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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.
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