• Continuous ORP monitoring — 30 mV accuracy, 1 mV precision, read live in the ReefBeat app rather than spot-checked with a kit.
• Dual ceramic double-junction electrode — a design chosen for stability in reef water rather than a generic single-junction probe.
• Calibration lives on the probe — its calibration data is stored on the probe itself, so it can move to another ReefControl controller without recalibrating.
• Bluetooth validation — check and validate the reading from your phone without pulling the probe out of the water.
• Feeds automation — paired with ReefControl Power, an ORP reading can drive things like ozoniser control.

Red Sea does not publish a stated measurement range (mV span) for this probe — only the accuracy and precision figures above.

In the box: one ReefSense ORP Probe.

Not included: the 460 mV reference solution (Red Sea part R35854) used for periodic validation, and the ReefControl Lite or Pro controller this probe plugs into and depends on. Without a controller, this probe has nowhere to send its readings.

Suitable for marine and reef systems already running, or being set up with, a ReefControl Lite or Pro controller — particularly where you're dosing, running ozone, or want an early read on overall water quality trends.

Not suitable as a one-off spot check — ORP electrodes are wear items with a limited service life, so this suits reef keepers who want continuous trend data, not an occasional reading.

Validate the probe against the 460 mV reference solution roughly every 2 months, over Bluetooth, without removing it from the water. Because the electrode wears with use, expect roughly 12 months of continuous service before it needs replacing. The classic end-of-life sign is a reading that stops reacting to real changes in the tank — if that happens, the probe needs replacing rather than recalibrating.

• ReefControl Lite or Pro — the controller this probe requires to operate.
• ReefSense pH & Temp Probe and ReefSense Salinity & Temperature Probe — build out a fuller picture of water chemistry on the same controller.
• ReefSense Magnetic 4-Probe Holder — mounts this probe alongside up to three others at a consistent depth.
• ReefControl Power — lets an ORP reading drive automations such as ozoniser control.

Red Sea covers the ORP probe for 6 months as a wear item, shorter than the 24-month warranty on non-wearing ReefSense accessories, in addition to your rights under Australian Consumer Law. Small, lightweight item — standard parcel delivery.

Do I need anything else for this probe to work?

Yes — a ReefControl Lite or Pro controller. The probe has no display or connectivity of its own; it plugs into one ReefSense port on the controller.

Why is the warranty only 6 months when other ReefSense sensors get 24?

The ORP electrode is a wear item — its ceramic junctions degrade with continuous use, typically over about 12 months, unlike the non-wearing salinity probe or leak detector.

How do I know when it needs replacing?

The classic sign is a reading that stops moving when the tank's actual redox changes — if validation against the reference solution can't bring it back in line, it's due for replacement.

Can I move it to a different ReefControl controller?

Yes — calibration data is stored on the probe itself, not the controller, so it carries its calibration with it.