Hanna I70300L storage solution for pH and ORP electrodes

I70300L is a storage solution prepared with reagent grade chemicals that can be used to ensure optimum performance of your pH and ORP electrodes.

• Special formulation to minimize microbial growth and osmotic/diffusion effects between the solution and inner reference electrolyte
• Clearly marked expiration date and lot number for traceability.
• Designed for storing any pH or ORP electrode.

HI70300L is a pH storage solution that can be used to store your pH electrode*. To ensure an optimum response time, the glass sensor tip and the reference junction of the pH electrode should be kept moist and not be allowed to dry out when not in use. Placing the pH electrode in a small glass filled with storage solution or replacing the solution in the protective cap is a suitable way to store the electrode. The HI70300L should also be used to rehydrate the electrode after a cleaning procedure by soaking for at least one hour before taking measurements. * Never store pH or ORP electrodes in distilled or deionized water. Doing so will shorten the life of the sensor.

Air tight bottle with tamper-proof seal

• Ensures quality and freshness of solution

Each bottle marked with lot number and expiration date.

• Hanna pH storage solutions are specially formulated to have an expiration of 5 years from manufacture for an unopened bottle.

Q&A

What is pH electrode storage solution?

pH electrode storage solution is a specially formulated liquid used to keep pH and ORP electrodes hydrated when they are not in use. It maintains the moisture of the glass sensing membrane and reference junction, which helps ensure accurate and reliable measurements over time. 

Why should pH electrodes be stored in a storage solution?

Storing pH electrodes in a proper storage solution prevents the glass membrane from drying out, protects the reference junction, and minimizes microbial growth or osmotic effects. If electrodes dry out, their response time and accuracy can deteriorate and their lifespan may be shortened. 

Can distilled or deionized water be used to store pH electrodes?

No. Distilled or deionized water should not be used for storing pH electrodes because it can draw salts out of the reference electrolyte, damage the electrode, and shorten its life. Always use a dedicated storage solution or manufacturer‑recommended alternative. 

When should you soak a pH electrode in storage solution?

After cleaning or calibration, electrodes should be soaked in storage solution—typically for at least one hour—to rehydrate the glass bulb and reference junction before taking new measurements. 

What is inside a typical pH electrode storage solution?

Most storage solutions are potassium chloride (KCl)‑based formulations designed to maintain a consistent ionic environment, minimize bacterial growth, and protect the reference system. Laboratory and industrial variants may include additional chemicals based on manufacturer specifications. 

How do you store a pH electrode with storage solution?

For handheld meters, fill the protective cap with storage solution and place it over the electrode tip. For benchtop probes, immerse the glass bulb and junction in a small beaker of storage solution. The electrode should remain moist at all times between uses.

How long can a pH electrode be kept in storage solution?

pH electrodes can be kept in storage solution for both short‑term and long‑term periods as long as the solution covers the sensing elements and does not evaporate. Replace the solution periodically and follow manufacturer recommendations for maximum storage duration. 

Can storage solution also be used to refill refillable probes?

Yes. Many potassium chloride‑based storage solutions also serve as refill fluids for compatible refillable pH electrodes, helping maintain the internal reference electrolyte and proper function, especially for longer storage intervals.