Apex PH probe. Saltwater or Freshwater PH

[ReefHunter006]

I recently heard that saltwater PH needs a correction of about .15 with the probes we have in the hobby because it measures “fresh water PH” and “saltwater ph” needs a -.15 correction, something referred to as a fh correction. I was unable to find any literature or support for this. So I was curious if anyone had any further input on the subject.

If so, I may just leave my ph where it’s at.

I’m aware of the majority of opinions on proper ph levels. The apex probe is calibrated quarterly. I’ve seen no negative side effects at this point. This is from my predominately sps frag system.

 

[blaxsun]

My Apex probe is pretty much spot on when I test with my Hanna pH probe. In any event, as far as I know there's no easy (or cheap) way to recalibrate the Neptune pH probe or adjust it like you can the temperature or salinity probes,

 

[All_talk]

You do need calibration solutions, but calibrating the probe in not terribly difficult.

Connecting and Calibrating Your pH Probe to a Neptune Systems Apex

Once you have mounted your Apex, connected it to your network and updated your Apex Operating Software, then you are ready to begin configuring the settings in your new Apex. However, DO NOT proceed any further in the setup process if you have not yet updated your Apex Operating System (AOS).

www.bulkreefsupply.com

 

[Randy Holmes-Farley Verified Community Expert]

I recently heard that saltwater PH needs a correction of about .15 with the probes we have in the hobby because it measures “fresh water PH” and “saltwater ph” needs a -.15 correction, something referred to as a fh correction. I was unable to find any literature or support for this. So I was curious if anyone had any further input on the subject.

If so, I may just leave my ph where it’s at.

I’m aware of the majority of opinions on proper ph levels. The apex probe is calibrated quarterly. I’ve seen no negative side effects at this point. This is from my predominately sps frag system.

No, you should not be using a correction unless you are a chemical oceanographer and are using a special pH scale where certain chemical principles hold (e.g., concentration of H+ and OH- are the same at pH 7).

All reef hobbyists use the normal NBS scale using standard buffers and no corrections.