tikalize
Member
When i purchased my EX i already had a Pinpoint ORP probe on hand so i hooked it up & calibrated it in the GHL solution. It calibrated fine & read 200mv. I had it in my sump for some time now. The first couple of months my ORP was between 300 & 350. Now my probe is reading between 700 & right now as i speak it is up to 933! I also clean my probe on a regular basis & have recalibrated it with no problem. Could this be a possible defective probe or have you guys ever head of a ground loop problem with ORP measurements? Just checking before i try to replace something that's not broke. Thanks.