ORP issues

[serpentman]

I am currently using an ORP probe with a PX1000 connected to an AC3 and am getting very strange results. My ORPA is reading ~35mv.2-5. I have a separate Pinpoint meter that is showing 410mv.2-5. I have switched probes to make sure one wasn't faulty to no avail. I would very much like to believe my Pinpoint as the 35mv.2-5 is concerning.

My only thought is there is an issue with the PX1000 or my calibration. Any ideas?

[kenargo]

it's reading 35 or 350; just checking. Double check that the port on the PX1000 is set to ORP and not PH (settings, ORP, select ORPA and verify that it is enabled).

[serpentman]

Its reading 035. I did verify that the ORPA was enabled. Very strange....

[kenargo]

I've never seen a new probe read this low, usually a new probe reads in the low 100s and it takes about a week in tank water before is reads accurate. You might want to call Neptune and see what they think or you might want to give it a couple days and see if the probe readings start raising as the probe becomes fully wetted.

The probe isn't close to other probes? Have you tested it in a cup of tank water; that's always a good test?

[serpentman]

I tried it in other parts of the tank as well as in a cup. I also tried in a glass of FW and it went up to about 065.

I suspect the problem may be with the PX1000.

[Cwater]

What was the resolution on this? I just received a brand new Lab Grade ORP Probe at it is reading 040 or so in my sump. I then tried it in Ocean water and it now reads 088. How long should it take to break in? Do you think my probe is working properly?

[swearint]

My experience with the standard ORP probe tracks pretty close to what Ken described. Looking at my ORP graph from initial setup, it first read ~140 and over about 14 hours ramped up gradually to around 300. Now it cycles from around 310 to 340.

How long has it been reading low, and is it gradually rising? If has been that low for more than several days, I suspect a bad probe.

Todd

[serpentman]

No resolve yet. I think I need to send the PX1000 in. I am getting crazy pH readings as well.

[Cwater]

I guess that I need to be a little more patient. The ORP reading is currently at 260. Hopefully, it will keeping going up over the next few days.