Long Body pH Electrode with BNC Socket Probe 300cm Cable 0-14pH for pH Meter, pH Controller pH Device Economical Sensor

I used it to replace the probe on my Bluelab Guardian with no issues. Calibrated with no problem and has been working for a few months now. Quick accurate readings is all I can ask for and so far this thing is delivering at a fraction of the cost of Bluelabs probe. I'll update with any issues.

Purchase this replacement probe for my blue lab combo meter and it works smoothly.

Purchased as a replacement probe for my BlueLabs device. The electrode connected and calibrated perfectly and is giving consistent accurate readings. I don't know what the longevity will be, but at a fraction of the cost for a Bluelabs replacement, even if it lasts 1/2 as long it's still worth it.

It worked great if you’re testing and one of your test shows error just press on and come back to it. Once it gets a different foundation of the other calibrating test it should register.

For the money these probes work very good completely submersed. I calibrate every 10 days. I normally get 60 days use before latency in readings begins to be a problem. At about the 60 day marek the probes takes 2-3 times longer to report accurate PH. Specifically PH values between 5.5-6.0. If you are running auto PH systems this can be a problem. As the reservoir gets low and the PH swings high and the dosser dumps PH down to correct and that throws out the PH during feeding. When this occurs, time to replace.

Works as it should

Don’t buy it. I setup a new tank, during cycle, no fish just bacteria. Reading from this probe is much lower than double junction probe. See picture. Reading low compared to Milwaukee probe. Take forever to catch up, after multiple calibration still reading low

It is working on my Ph meter. But accuracy is not good enough during testing with standard buffer.