WTBorrow known good ORP meter

[ctenophore]

All,

I'm convinced that there is something up with my AC3 and the expansion box. I had sent it in to Neptune because my last ORP probe was reading 79. Neptune told me it was a bad probe, even though it was new, right out of the box (it had been in the box for nearly 2 years as my backup). So I ordered a new probe. Installed it last week, and it now reads 190-200. Supposedly they don't need calibrated, but is my ORP really that low? To make things even more confusing, I have a Pinpoint ORP controller with one of the bulk reef supply cheapo ORP probes, which reads 320. But that controller is really old, has a bad relay which causes it to buzz as the outlet cycles on and off at 60Hz. So I don't fully trust it's reading. I took that BRS probe and put it on my AC3's PX1000 expansion, and it now reads 193-198, which is in agreement with the new probe.

 

So, I'd like to borrow somebody's known-sane meter for a few days if possible, to see if either my ORP is really that low (I just fired up my big ozone reactor last week) or if Neptune was giving me a bad diagnosis. Obviously the closer to Rockville the better, but beggars can't be choosers

 

Thanks for any help,

Justin

[dtfleming]

Buy some pinpoint redox and recalibrate.

[ctenophore]

Buy some pinpoint redox and recalibrate.

I have a packet of it, but not sure if it is the quinhydrone solution that Neptune suggests. Also, Neptune uses a 2-point calibration with quin-4 and quin-7. So I'd have to find quinhydrone which is not cheap stuff, and mix up saturated solutions with pH 4 & 7 buffers.