Bluelab Replacement pH Probe - For Combo and Maestro Meters
Best for: Bluelab Combo or Maestro meter owners whose original pH probe has been damaged, lost or has simply worn out.
Our thoughts
Probes are the one part of any pH meter that wears out eventually, however careful you are - it's just how the sensor chemistry works. This replacement means you don't need to bin a perfectly good meter body just because the probe's had its day.
If your original Bluelab probe gets damaged or lost, this replacement pH probe is compatible with Bluelab Combo and Maestro meters. Like the original, it's fully waterproof, easy to clean and built with a tough polypropylene barrel for durability in grow room conditions. It comes with two metres of cable and a suction cup included, so you can permanently mount the probe in a reservoir for continuous testing rather than dipping it in and out by hand.
How it compares
As a genuine manufacturer replacement part, the real comparison is against third-party or generic probes.
- Versus a generic aftermarket pH probe, this is built to Bluelab's own double-junction design, which is generally more resistant to fouling from nutrient solution than cheaper single-junction probes.
- Versus replacing the whole meter, swapping just the probe is significantly cheaper when the display and electronics are still working fine.
- Versus competitors like Hanna or Milwaukee's own replacement probes, Bluelab's two-metre cable and included suction cup make permanent reservoir mounting straightforward without buying extra accessories.
If your Combo or Maestro's display is still good, this is the cheaper, sensible fix over a full replacement.
Usage guidance
Fitting and calibrating a replacement probe is quick once you know the steps.
Fitting
Unplug the old probe from your Combo or Maestro meter and connect the replacement in its place, following your meter's manual for the exact connector.
Calibration
Calibrate the new probe with pH 4.0 and 7.0 buffer solution before relying on it for readings, as every probe needs its own calibration once fitted.
Mounting
Use the included suction cup to fix the probe permanently inside a reservoir if you want continuous monitoring rather than manual spot checks.
Care
Keep the probe tip in storage solution when not submerged, and rinse it after exposure to strong nutrient solution to extend its working life.
Technical specifications
- Compatible with: Bluelab Combo and Maestro meters
- Probe type: double-junction pH probe
- Barrel material: polypropylene
- Waterproof: yes
- Cable length: 2 metres
- Mounting: suction cup included
Who this is for
- Combo or Maestro meter owners with a damaged, lost or worn-out original probe
- Growers wanting to permanently mount a probe in a reservoir using the included suction cup
- Anyone wanting a genuine manufacturer part rather than a generic aftermarket probe
- Growers keeping an existing meter body running rather than replacing the whole unit
Best suited to existing Combo or Maestro owners needing a straightforward, compatible fix.
Our take
A probe wearing out is normal, not a sign your meter's failed - this replacement gets you back to accurate readings without the cost of a whole new unit.
Worth picking up if you want straightforward, reliable readings restored without overcomplicating things with a generic part.
