Neptune pH Probe
Neptune pH Probe
Neptune now offers both the pH and ORP probes in a double-junction construction for the Apex controller - these probes are built so they hold calibration longer and have a longer lifespan than single-junction probes.
Single junction probes put the reference electrode in direct contact with aquarium water. Over time, the junction will slowly leak aquarium water into the electrolyte which changes the accuracy of the probe and requires more frequent calibrations.
Double junction probes place a second vessel inside the main electrolyte with a second internal junction. The means that even when the aquarium water eventually begins to make its way in the first compartment, it still has to go through the second junction to contaminate the electrolyte surrounding the reference electrode.
These probes will not only work with your Netpune Apex but virtually any other controller or monitor that uses BNC connections.