Apex + Mettler Toledo PH probe

[SecondCityCorals]

Try as I might, my PH probe from Apex is terribly off by up to 0.3. Even after calibration, it drifts within a week. My cheap $20 Amazon PH probe does better than the Apex.

I'd like to get a pair of probes I can truly rely on. I'm going to be adding a calcium reactor soon and will be turning the reactor on/off by the PH level in the reactor. And if that level isn't stable. My tank wont be stable.

I don't want to take the risk. I'd rather spend $400 on a pair of rock solid PH probes than risk losing all my SPS. Has anyone done this? Is this a common problem with Apex probes where they drift so far? Thanks.

 

[Ranjib]

pH probes (and DO /ORP /EC probes) are very prone to inaccurate results from electrical interference, calibration issues (including temperature compensation) and manufacturing glitches. BRS double junction probe is a good one. I won't recommend chasing pH if your coral looks healthy. This has been reiterated numerous time in this forum, and our learning is Alkalinity is more important, pH needs to be within a range, thats all.

 

[Randy Holmes-Farley Verified Community Expert]

IMO, the problem may not be the probe, but the controller. I agree they are very prone to issues that likely include electrical interference