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Neptune Systems

Lab Grade Double Junction pH Probe

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Out of stock
SKU
210223
Rating:
76% of 100
1  Review Add Your Review
$119.99 $119.99

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Details

Neptune Double Junction probes will out last most other traditional lab grade probes letting you go longer between calibrations, and having to purchase and replace probes less frequently. The Double Junction isolates the reference gel and probe from proteins and other organics that may otherwise precipitate and clog, shortening the lifespan of the probe.

  • Longer lasting
  • Reliable readings
  • Quality connections
  • BNC style connector

 

Neptune's Double Junction pH Probe is compatible with any monitor or controller with a BNC style connection. If you just need to replace your worn out probe or add another you will not be disappointed with the double junction feature of these probes. Most probes have a single chamber to house the actual reference probe and fluid that can become contaminated quickly throwing off readings and requiring calibration quite often. The double junction probes have two chambers that keeps any contaminants that could possibly react with and clog the actual sensing portion of the probe.

 

Whats Included?

1x Double Junction Lab Grade pH probe w/ 10' cord

 

Note: We suggest calibrating probes every 60-90 days for reliable and stable readings. Calibration fluid sold separately.

More Information
More Information
SKU 210223
UPC 019962173950
Aquarium Type Saltwater, Freshwater
Reviews 10
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You're reviewing:Lab Grade Double Junction pH Probe
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Product Questions

Product Questions

Would this probe be able to connect to an Arduino Microcontroller? My understanding is that the probe must have a connector with pins for power (VCC, 5V, or 3.3V) and ground (GND), which connect to the Arduino's power and ground pins. It also has to provide an analog output (PO) that connects to an analog pin on the Arduino. Would this probe be able to do this?
Question by: Ruby on Oct 23, 2025, 11:29 AM
Hi Ruby,

Thank you for reaching out! That is a great question. Our probes use a BNC connection, so if your board/controller had this, then it should work fine!

Happy Reefing!
Answer by: Kristen Macdougall (BRS Staff) on Oct 23, 2025, 2:17 PM
What is the average life of this pH probe, in general how often do they need to be replaced?
Question by: JT on Nov 20, 2022, 9:58 AM
Thanks for reaching out! It is good to calibrate them ever couple of months and replace them once a year!
Answer by: James Johnson (BRS Staff) on Nov 26, 2022, 10:49 AM
Thanks for the question! The life span varies on these probes, but most that I have used last anywhere from 1-3 years before needing to be replaced. You'll know it's time when you calibrate and the probe still won't read 7.0 in the 7.0 calibration packet. Please let us know if we can help with anything else!
Answer by: Kyle Thomas (BRS Staff) on Nov 26, 2022, 10:50 AM
Do you sell the calibration solution for recalibration of the ph probe?
Question by: Richard on Dec 28, 2017, 9:54 PM
Thanks for reaching out to BRS!

The following link will take you to our product page for Milwaukee pH calibration fluid. Have a great day! https://www.bulkreefsupply.com/milwaukee-ph-calibration-fluid-single-use-packet.html
Answer by: Josh Cuta on Jan 2, 2018, 1:24 PM
What is the shelf life for unused ph probes?
Question by: Brian Buschmann on Nov 21, 2017, 7:47 AM
Hey there,

So long as the probe remains properly stored in the reference solution, it can remain usable for up to 5 years from the date of manufacture.

Have a great day!
Answer by: Zack on Nov 24, 2017, 11:01 AM
Do these work on the older apex systems?
Question by: Josh Avila on Jul 14, 2016, 2:09 PM
Hi Josh,
Thanks for the question and the Neptune Double Junction probes will work with all Neptune Apex systems. All you need is an open BNC connector for a pH probe. If you are replacing an old pH probe all you will need to do is calibrate the new probe once you get it hooked up. : )
Answer by: Charlie on Jul 14, 2016, 2:49 PM
Will this probe work the a reefkeeper lite setup?
Question by: Jim on Jul 14, 2016, 2:03 PM
Hi Jim,
The Neptune Double Junction probes are compatible with any type of controller like the ReefKeeper Lite. All you need for your RKL unit would be a module that can accept a pH probe like the SL1 or SLX module.
If you have any other questions just let us know.
Answer by: Charlie on Jul 14, 2016, 2:55 PM

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