Bluelab Replacement pH Probe | Double Junction BNC Electrode, 2 m Cable

When to Fit a Bluelab Replacement pH Probe

A pH probe is a consumable rather than a thing that breaks. The glass and the reference junction change chemically as they work, and past a certain point no amount of cleaning brings the reading back. The symptoms are consistent enough to name. A number that takes longer and longer to settle. A slow drift away from a known buffer. A probe that will not hold a two point calibration after a proper clean. Bluelab asks for calibration once a month, and more often under heavy use, continuous monitoring, or organic nutrients. Between readings the tip lives in KCl storage solution, refreshed weekly. A probe that has dried out is not automatically finished. It needs rehydrating and a fresh two point calibration before the numbers mean anything again.

Fitting a Bluelab Guardian pH Probe or a Meter Probe

This is the same electrode across the range, so it goes into any Bluelab instrument with a BNC connection. That covers the Combo meter, the handheld pH meters and the Guardian monitors. The cable is 2 metres, or 6.6 feet, in a polycarbonate body with a waterproof joint. The reference is double junction, which is what buys it a longer working life than a single junction electrode in a nutrient tank. It is gel filled and non-refillable, so there is nothing to top up and nothing to service beyond cleaning. Two limits are worth knowing in advance. It works between 0 and 60°C. It also wants a solution of 0.2 EC or above, so pure water and fresh reverse osmosis give it too little to read. A probe holder with a suction cup and a KCl filled storage cap come in the box.

Key Features

• Fits the whole BNC range: Combo meters, handheld pH meters and Guardian monitors all take this probe.
• Replace the probe, not the meter: A worn electrode is a consumable. The instrument behind it is not.
• Double junction reference: Longer working life in a nutrient tank than a single junction electrode.
• Gel filled, non-refillable: Nothing to top up. Cleaning is the whole of the maintenance.
• 2 metre cable: Or 6.6 feet, in a polycarbonate body with a waterproof cable joint.
• Needs 0.2 EC or above: Pure water and fresh reverse osmosis give the probe too little to read.
• Works from 0 to 60°C: Outside that band the readings stop being reliable.
• Holder and storage cap included: A suction cup holder, plus a KCl filled cap to keep the tip wet.
• Calibrate monthly: More often under heavy use, continuous monitoring or organic nutrients.
• Six month warranty: Bluelab's standard cover on a replacement probe.

Technical Specifications